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NOTICES TO CORRESPONDENTS.

D. A., J. M., Arcanum, H. M. Prideaux, J. P. Taylor, J.
Watkinson, Brother Bob, W. F. A C. Pearson, R. H. M.,
and J. G. Finch. The Black Pawn at Black King's fifth
should be a White Pawn. The problem is quite sound. If
B to K Kt 3 B to Q 4 B to K 6
if 1.
if 1.
Kt to B 5
B to B 5
B to R3'
P to Q 3
Q takes Q
; if 1.
Kt takes BP
Kt to Kt

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CORRECT SOLUTIONS to 442 and 443 by D. A. (Dublin),
J. G. Finch, and J. Marshall; also to 443 by Arcanum.
B. H. PRIDEAUX.-Thanks for corrected version of the
problem.

ABRIDGED REPORT OF THE JUDGES OF THE BRITISH
CHESS ASSOCIATION.

The first prize is awarded to J. H. Finlinson: set-"Ex
Budore Voluptas." The second to F. F. Lamb: set-
"Anything." Prize for two-mover to J. Paul Taylor-
No. 1 of "Home, Sweet Home." Prize for best three-
mover, W. Coates: set-" Qui se ressemble," &c. Prize
for best four-mover, C. Callander: set-"Es griebt,"
&c. The absolutely best four-mover was No. 3 of
"Qui se ressemble," &c.; but as the composer of that
set takes the three-move prize, the four-move prize
is awarded as above.

ANS VERS TO CORRESPONDENTS.

All communications should be addressed to the EDITOR of the ENGLISH MECHANIC, 31, Ta.istock-street, Covent Garden, W.C.

HINTS TO CORRESPONDENTS.

1. Write on one side of the paper only, and put drawings for illustrations on separate pieces of paper. 2. Put titles to queries, and when answering queries put the numbers as well as the titles of the queries to which the replies refer. 3. No charge is made for inserting letters, queries, or replies. 4. Commercial letters, or queries, or replies are not inserted. 5. No question asking for educa tion or scientific information is answered through the post. 6. Letters sent to correspondents, under cover to the Editor, are not forwarded; and the names of oorrespondents are not given to inquirers.

The following are the initials, &c., of letters to hand up
to Tuesday evening, October 1, and unacknowledged
elsewhere:-

FOSTER AND WILLIAMS.-T. E. Morris.-G. and T. Vesper.
-H. T. Cassini.-W. Field.-C. C. Hawks.-C. T. 8.-
St. Clair.-Sidney Jewsbury.-M. J. W.-Lux.-Gode-
man.-Wm. Smith.-C. E. M. E.-Asher.-A. B. Hard-
ing.-E. K. Elliott.-A. S. Baskett.-W. B. Prideaux.
Seanpee.-W. B.-Cymro.-R.-W. H. O.-Glatton.-
Observer.-D. W. B.-Old Flute.-Charles L. Hett.-
Glenmaquoich.-J. L.-E. L. Stockport. - March
Brown.-Albert Hall.-A.W.-Heat.-Sanitary Science.
-H. Turner.-Leveran.-Clock Springs.-Technical.-
W. T.-F. C. Dennett.-J. N. D., Tuxford.-Spiegel
Eisen.-W. Johnson.-A Mechanic.-Lancashire Lad.
-J. L.-H. Mackenzie.-J. J. B. C.-J. H. Griffin.-
John Steel.-C. Harding.-F. R. A. 8.-Geo. Wright.-
Achilles.-Zinco.-A. D. R. J.-One in a Fix.-G. B. S.
-Ernest Sprague.-W. Granger.-Z.-T. E. M.-Lan-
cashire Fitter.-L. S. A.-Jack.-G. Newton.-A. J.
Palmer.-John Manford.-F. A. Gower.-W. Waghorn. |
-W. Chamberlain.-J. H. Rawlins.-J. and W. Arch-
butt.-Rev. A. Bond.-J. C. Frank.-H. Livesey.-
Bayliss, Thomas, and Co.-G. Davies.-T. Fletcher.-
G. H. Aubrey.-Hughes and Co.-A. Ledger.-Leray
and Co.

Lloyd's Scholarship in Naval Architecture or Marine Engineering. - The Lords of the Admiralty having accepted an offer from the Committee of the Lloyd's "Register of British and Foreign Shipping" to establish an annual scholarship of £50 a year, tenable for three years, to be competed for by private students of naval architecture or marine engineering at the Royal Naval College, have issued the following regulations as to the competition for this scholarship: Candidates desiring to compete, being British subjects, must apply to the Secretary of the Admiralty, Whitehall, to enter the Royal Naval College, as private students of naval architecture or marine engineering. They will be required to pass satisfactorily the entrance J. examination for private students. Candidates who Tas satisfactorily the entrance examination will subsequently undergo the further examination laid down for competitors for the Admiralty free studentahip. The candidate who stands first in order of

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Subscribers receiving their copies direct from the office are re quested to observe that the last number of the terra for whion their subscription is paid will be forwarded to them in a PINK Wrapper, as an intimation that a fresh remittance is necessary, if it is desired to continue the Subscription.

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TO AMERICAN & BELGIAN SUBSCRIBERS

American and Belgian Subscribers, especially when renewing their subscriptions, are particularly requested to advise the Publisher of the transmission of the Post-office order, and the exact amount for wash it is made payable. If the last-mentioned precaution is omitted, some dimoulty is very likely to occur in obtaining the amount

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The remittance should be made by International Post-office order. Back numbers cannot be sent by the ordinary newspapes post, but must be remitted for at the rate of 4d. each to cover extra Dostage.

us stroll to the Euston-road, hard by the Regent's Park, to Epps's
EPPS'S COCOA.-All the Year Round says-"Let
Cocoa Manufactory, where may be studied the making of oooos
articles, not as luxuries, but as actual food"
on a stupendous scale, giving a just idea of the value of these

vast extent of the industry may be gained from the fact that one
EPPS'S COCOA.-John Bull says-"An idea of the
firm alone-that of Messrs. Epps & Co.-now sell some 4,000,000
pounds annually."

EPPS'S COCOA.-Christian World says:-"If I

am to take cocos," said I, "I must see and judge for myself what are the ingredients of which it is composed; with this view I made my way to the cocoa manufactory of James Epps & Co., in the Buston-road."

EPPS'S COCOA.-"Cassell's Household Guide" says "We will now give an account of the process adopted by Messrs. James Epps & Co., homoeopathic chemists and manufac turers of dietetic articles at their works in the Euston-road London." EPFS'S COCOA.-Morning Advertiser says hitherto been almost prohibitive, were greatly reduced, and one "Nearly two centuries after, in 1832, the duties, which had of the first to take advantage of re-establishing the popularity of cocoa was Masers. Epps & Co., the homoeopathic chemists."

TERMS OF SUBSCRIPTION.

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Subscribers are requested to order Cases and Vols. through their booksellers, and noc to send direct. The regulations of the Post-offios prevent their transmission through the Poss.

Holloway's well-known and highly-esteemed Pills put the power of removing his infirmity within the grasp of every invalid. Martyrs to indigestion who are daily becoming weaker and worse may make themselves stout and strong by taking these medicines in the doses plainly indicated in their accompanying directions.

CHARGES FOR ADVERTISING.

Thirty Words

Every additional eight words...

R. LILLIE. (We cannot understand your sketch at all.
Get some mechanical friend to write a query plainly y part of the United Kingdom.
and we will insert or reply to it.)-AMATEUR. (Address
him through the publishers, Messrs. E. and F. N. Spon.)
-H. A. H. (Surely you have not read the letters on
the gas-engine which appeared on pp. 63, 99, 291, 316,
346, and 367 of the last volume, and were continued
from the preceding one.)-A., Liverpool. (Yes, or any
other decaying vegetable matter.)-W. B. O. (There
are many causes and many remedies, but unless you
can say what is the former we fear we can hardly assist
you.)-J. GRAY. (See our reply to "Jasper" on p. 5,
in No. 702.)-BETA. (The disease is not invariably
hereditary, although it is frequently so. The symptoms
seldom manifest themselves before the age of 45, and
before they actually appear no physician could apply
any test of the kind you mention. You have no reason
to abstain from the course you mention, but, on the
contrary, may reasonably hope to escape any ill effects
by temperate living and careful attention to general
health. Remember especially that undue indulgence in
alcoholic stimulants is a provocative of the disease, and
invariably aggravates its symptoms.)-BIRMINGHAM.
(Those advertised in these columns by J. Francis are
handy and easily managed.)-UNSATISFIED. (An old
sailor's yarn in our opinion.)-A. I. T. (Try the appli-
cation with a sponge of liquid ammonia very consider-
ably diluted with water. This will remove the grease.)
-TRUSTEE. (We do not see how any outsider can
possibly answer the question. If you mean what com-
pulsory steps must you take, you had better consult
your solicitor.)-FLOATING BOGUS. (We never heard
of it. There is the Sewing Machine Gazette, published
at 11, Ave Maria-lane, E.C.)-COOK. (All queries
asking "where can be obtained" the articles named,
are advertisments, and must be paid for as such if in-
serted.)-J. HEPPELL. (The information is probably
of a private nature, but whether or not, if you are to
receive it you must, as the correspondent who replied to
you stated, advertise your address.)-RECRUIT. (Better
write to the editor of the Volunteer Service Gaze te.)
VALVE. (See note to letter 14906, p. 74.)-PIVOT.
"Gore's Electro-Metallurgy," published by Longmans;
"Sprague's Electricity," Spon; and " Watt's Electro-
Metallurgy," Crosby Lockwood.)-A STUDENT. (Text-
books are generally recommended in the Calendar, and
if a descriptive geometry is mentioned, you would do
well to use the one specified. Failing that, any of
the educational publishers can supply one.)-R. RAN-
GER. (See advt. on front page, Sept. 13, and p. 384,
Vol. XXIII., for a full description.)
BROWN, Fred. Stanley, 52in. Excelsior, Ferox, Noble,
Stud, Leicestershire, New Subscriber, Wallasey.-See
Inst. C.E., Inquirer, A. U. L, J. W.. E. W. Vin-

Front Page Advertisements Five Shillings for the Arst 40 words,

afterwards 8d. per line. Paragraph advertisements One Shilling per line. No front page or paragraph advertisement inserted for less than Five Shillings.

indices to back vols.

TELEGRAPH, Test Valley, Colonial, Cook.-Your queries

are advts.

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merit amongst those who gain free studentships will C. G., J. L. H. S., Samuel Smither, W. J. Clark, C. Lark, ENGLISH MECHANIC WANTED,

be awarded the Admiralty Scholarship; and from the remaining ones the Committee of Lloyd's "Register" will, at their discretion, select either the candidate who stands first among the students of naval architecture or the first among the students of marine engineering, to receive the Lloyd's Scholarship of £50 per annum, tenable for three years, provided that the conduct and progress of the student are satisfactory. The selected candidate will retain the advantage of the free studentship which he had gained by competition. The candidate selected by the committee will enter the Royal Naval College on the 1st October next following the before-mentioned examinations, and remain there for three Sessions, undergoing the full course in naval architecture or marine engineering as may be determined by the committee, He will reside outside the college.

Clericus, and others have replied to queries already
similarly answered.

The Largest Circulation of any Professional
Journal in the Kingdom renders the BUILDING NEWS the best
medium for all advertisers of Building Materials, Artistic require
ments, and Contractors' Machinery, and for all those seeking
situations as workmen. The number and excellence of its illus.
trations render it the unrivalled representative of the progress
Among its contributors are the leading architects and art critics
of the day, and no trouble or expense is spared to make it the
nected with the Arts of Construction and Design.
most accurate and comprehensive guide to all information con-
Frice Four-
pence, of all booksellers and newsvendors. Post-free 4. Office,
11, Tavistock-street, Covent-garden, W.O.

of modern art, and the most complete record of ancient examples.

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Professor FRANKLAND, D.C.L., F.R S., commenced a course of forty lectures on INORGANIC CHEMISTRY on Wednesday. the 2nd October, at 10 o'clock, to be continued on each succeeding Friday, Monday, and Wednesday at the same hour. Fee for the course, £4; laboratory practice for 3 months, £12. eighty lectures on BIOLOGY, or NATURAL HISTORY (including Paleontology) on Wednesday, the 2nd October, at 10 o'clock, to be continued on every week day but Saturday, at the same hour. Fee for the course, £4; for the laboratory practice, £6. Professor GUTHRIE F.R.S.. commenced a course of about sixty lectures on PHYSICS at half-past eleven on Wednesday, the 2nd October, to be continued at the same time on every week

Professor HUXLEY, L.L.D., F.R.S., commenced a course of

£12.

Lamplough's Pyretic Saline is refreshing, day but Saturday. Fee for the course, £4; laboratory practice,
most agreeable, and the preventive of FRVERS, BILIOUSNESS,
MALL-FOX, SKIN DISEASES, and many other spring and summer

These lectures will be delivered in the Science Schools, Exhibi-
allments. Sold by chemists throughout the world and the tion-road, South Kensington.
maker, 113, Holborn Hill. Use no enbalitute.-[ADTT.]
TRENHAM REEKS, Registrar.

Now ready, in one vol., atlas folio, pp. 46 and 24 folding plates cloth, price 15s.

THE STARS IN THEIR COURSES.

A two-fold series of Maps, with a Catalogue, giving the magnitudes according to the B.A.C., Proctor, Argelander, and Heis, showing how to identify at any time of the year all Stars down to the 5'6 mag., inclusive of Heis, which are clearly visible in English latitudes. By THOMAS SEBASTIAN BAZLEY, M.A., Author of "Notes on the Epicycloidal Cutting Frame," and an "Index to the Geometric Chuck."

London: TRUBNER & CO., Ludgate-hill.

Third Edition, greatly enlarged, crown 8vo., 4s. 6d. (postage 5d.)

LOCOMOTIVE ENGINE DRIVING:

A Practical Manual for Engineers in charge of Locomotive Engines. By MICHAEL REYNOLDS Comprising, besides other additional matter, "A KEY TO THE LOCOMOTIVE ENGINE." "Supplies a want, and supplies it well."-Engineer.

CROSBY LOCKWOOD & Co., 7, Stationers' Hall-court, E.C.

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EMERY, BLACK LEAD,

EMERY CLOTH, GLASS CLOTH, GLASS PAPER, &c.
"Flexible Twilled"

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for Engineers, Sewing Machine, Lock, and Scale Makers, and all
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are required.

FLEXIBLE GLASS PAPER.

THE SCIENTIFIC BASIS OF MUSIC. Unequalled for Strength and Durability. Each Sheet Stamp

By W. H. STONE, M.A., M. B. Oxon, F.R.C.P. Being No. 11 of Novello, Ewer, & Co's. "Musio Primers." Edited by Dr. STAINER. 8vo., paper covers, Is., paper boards, 1s. 6d.

London; NOVELLO, EWER, & CO., 1, Berners-street, W.;
and 80 and 81, Queen-street, E.C.

NOW READY, PARTS XXI. TO XXVI., COMPLETING MR.
BOURNE'S EXAMPLES OF STEAM & GAS ENGINES.
Complete in One, Volume 4to, pp. 534, with 54 Plates and 35
Woodcuts, price £3 108, cloth,

EXAMPLES OF STEAM AND GAS

ENGINES of the most recent approved types as employed in Mines, Factories, Steam Navigation, Railways and Agriculture, practically described; with an account of all the principal projects for the production of Motive Power from Heat which have been propounded in different times and countries. By JOHN BOURNE, C.E. Author of a "Treatise on the Steam Engine," a "Treatise on the Screw Propeller," &c.

...To be had also in 26 Parts, price 2s. 6d. each. Subscribers are requested to complete their Sets.

London: LONGMANS & Co.

Price Sixpence, post-free.

COLLOGRAPHY for AUTOGRAPHIC

PRINTING; by which any one can Reproduce Writing or other matter to an unlimited extent, in any colour, with perfection, with AUTOGRAPHIC ILLUSTRATIONS.

A. PUMPHREY, Emily-street, Birmingham.

ARTLEY'S SYSTEM of PLAYING

HA

the PIANOFORTE or HARMONIUM WITHOUT LEARNING NOTES and without any other instructions. Price, stamps, 2s. 6d. post-free from Publisher, WALTER HARTLEY, 57, Rhodes-street, Halifax, Yorkshire.

PRACTICAL GUIDE for Warming

with Hot Water Pipes, illustrated, 19 stamps. Plumber and Pump-fitter's Guide, illustrated, 19 stamps, post-free.-T. ELDRIDGE, 54, Murray-street, Hoxton.

Now ready, with engravings, fscap. 8vo., 23. 6d.

SECTION-CUTTING;

a

Practical

Guide to the Preparation and Mounting of Sections for the Microscope, special prominence being given to the subject of Animal Sections. By Dr. SYLVESTER MARSH,

J. and A. CHURCHILL, New Burlington-street.

BOOKS FOR

AMATEURS. - The

Whole Art of French Polishing and Gilding, also the Amateur's Practical Guide Book, each post-free, 14 stamps.SMITHER, 63, Crescent-place, Hackney-road.

Fifth Edition, price 6d.

SELF HELP TO PATENT LAW.

Also, price la., COLONIAL AND FOREIGN PATENT LAWS by GEORGE DAVIES, C.E. Published at the Office for Patents 4, St. Anne's-square, Manchester, by GEORGE DAVIES, O.R. (late John Davies & Son). Established 1835.

PATENTS.-Mr. J. C. MEWBURN,

BRITISH, FOREIGN, and COLONIAL PATENT AGENT and CONSULTING ENGINEER, gives prompt personal attention to all matters entrusted to him. Handbook on Patents sent post free.-Offee for Patents, 169, Fleet-street, London.

and Warranted.

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Oscillating Steam Engines
saine price
WHBAILEY & COALBION WORKS SALFORD

NON-POISONOUS
PAINTS.

The Silicate Paints are used for House

and Ship Painting.

These Paints, owing to their extremely hard nature, and the absence of all Chemical action, thoroughly protect Iron from Corrosion and Wood from Decay.

Manufactured in every shade of colour.

THEIR CHARACTERISTIC FEATURES ARE-
1 Cot, being nearly equal in bulk and doing the work of 2cwt. Lead
Paints. Non-Poisonous.
Non-chemical action on Iron and other metal. Absence of all
free acid in their composition. Thorough protection of the Iron
in Ships, whether submerged or not. Their hard petrifying
nature. Their double covering properties, That they will stand
That they are
practically indestructible. Their great economy over Lead Paints.
THE LIVERPOOL SILICATE PAINT CO.,
LONDON-107,Cannon-street, E.C. LIVERPOOL-Seel-street.

NOTICE TO INVENTORS. vertical degrees of heat without blisteriny

Immediate Protection to all Inventors for £8 89. by JULIUS HALL, Patent Agent, 30, Chancery-lane, Author of "Practical Suggestions," FIFTH EDITION, just published, con taining a chapter on TRADE MARKS; a chapter on Method of Obtaining Letters Patent, and the Cost of same; a chapter con taining 130 PRACTICAL MECHANICAL MOVEMENTS, with explanation of each diagram; and a chapter on CAUTION TO INVENTORS. Post-free, 13 stamps.-90, Chancery-lane.

PATENTS.-Mr. E. P. ALEXANDER,

CONSULTING ENGINEER and PATENT AGENT 14, Bouthampton-buildings, London, W.C. (upwards of twenty years practical experience). BRITISH, COLONIAL and FOREIGN PATENTS obtained; DESIGNS and TRADE MARKS registered. Infringements investigated and advice given on Patent Law. Instructions free. PROVISIONAL PROTECTION, 23 88. Liberal terms to agents.

PATENTS FOR INVENTIONS.

Mesere. DAVIES & HUNT procure BRITISH and FOREIGN PATENTS at moderate charges. Full particulars given in the HANDBOOK FOR INVENTORS, to be had gratis from No. 5, Berle-street, Lincoln's Inn, London, W.C., and from No. 87, 8t. Vincent-street, Glasgow.

INVENTIONS PERFECTED, and all

kinds of Machinery manufactured by 8. SMITH, 204, High Holborn, London.

NOTICE TO INVENTORS

BREWER & JENSEN, Engineers and Patent Agents, con tinue to transact business connected with Patents and Registra tions at most moderate charges. INVENTOR'S MANUAL gratia and post free. Established 1844-Offices: 33, Chancery-lane, London.

PATENTS. NOTES FOR THE GUIDANCE

OF INVENTORS (Reprinted from Engineering), may be had, post-free for 7 stampa, from the Author, Mr. W. LLOYD WISE, Office for Patente, Chandos Chambers, Buckingham-street, Adelphi, London W.C.

PATENTS FOR INVENTIONS.

The Office for Obtaining Patents, 21, Cockspur-street, Charing-cross. Londen, supplies gratis on application a HAND. BOOK for the Guidance of Inventors, to enable them to securely obtain through that office Home Colonial, and Foreign Patents at fred and moderate charges.-Address, Mr. T. MORGAN, as above.

ELECTRIC BELLS.

24 inch, 78. Gd., with 40 yards wire, p.sh,
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J. M. THISTLETON & SON, 1, Old Quebec-st., Oxford-st., W.

SELIG, SONNENTHAL & CO.,

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IMPORTERS of the Genuine Morse

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The parallel vice, tool holder, and the slide box are adjustable to various angles, and the whole machine swivels on its hai Planes 8 by 4 inches with adjustable parallel vice and reversing feed motion. Complete, £12 108.

THE SCENOGRAPH.

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HAIR.
WHISKERS,

of Optical and Scientific Instruments, Mechanical Toys Model Engines, Steam Boats, Electric Machines, Magnets, Micro scopes Telescopes, Thermometers, Barometers, Spectacles Electric Bells, &c., Covered Wire for ditto. Secondhand Instru ments bought or taken in exchange. Goods forwarded securely packedupon receipt of P.O. Order or stamps.

MICROPHONES,

As devised by Professor Hughes, from 4s. to 21s.

22, MOORGATE-STREET STATION BUILDINGS, LONDON, EO

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THEODOLITES, Dumpy

Levels,

Compasses, Spectacles, Eye-glasses, Eye-preservers. Steel spectacles, pebbles (boughy)

Steel spectacles, crystals

Steel eye-preservers, D-shape sides
Steel eye preservers, wire gauze rims
Remittance with orders.

18193

- 15.68

... 78 --2108

MOUSTACHIOS, THE SCIENCE DEPOT AND EX

TO INVENTORS.-General Patent London houses, or direct from the proprietor, Mr. J. LATREILLE,

Office. Established 1830. G. F. REDFERN (Successor to FONTAINE MOREAU & Co.), 4, South-street, Finsbury, London; sleo at Paris and Brussels. Provisional Protection, 27; French Patent, £7 Belgian, L. Circular gratis.

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CHANGE.-Immense Stock of Electrical, Heat, Pneumatic, Optical, Mechanical, Photographic, Chen ical Apparatus: Survey ing, Drawing, and Surgical Instruments; Minerals, Books, Models, Diagrams; Lathes, Tools, Parts, Fittings, and Material New and second-hand, very cheap.

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The English Mechanic

AND

WORLD OF SCIENCE AND ART.

FRIDAY, OCTOBER 11, 1878.

ARTICLES.

REPORT OF THE COMMISSIONERS
OF PATENTS.

THE PRESERVATION OF THE SIGHT.*
HINTS on the preservation of the sight

patent will be obtained as speedily as the payable. During the interval above named law's delays permit, and it is tolerably cer- only 10 per cent. of the patents survived to tain that all or nearly all of them will the full term, so that we may fairly assume go to the "seal" and become full-blown that only 10 per cent. of the present applipatents, whereas of the 71 native applica- cations are really worth the expenditure of tions it is equally certain that a large £40. But let it be observed that a patent percentage will never go beyond the stage which brings its owner a fortune, and conof provisional protection. We shall pro- sequently runs the full term of 14 years, bably not be far wrong if we conclude that pays in stamps only £175, whereas one that nearly one-half of the patents granted in may fall still-born costs £25, and we see at this country are granted to the inventions once that while the former sum is vastly too of foreigners, who for our purpose are per- small the latter is much too large. In other sons resident beyond the boundaries of the words, it appears that, to encourage invenUnited Kingdom. We may suggest that a tion, the cost of a patent should be reduced large proportion of these inventions, both to almost a nominal sum, leaving the exBritish and foreign, are practically useless; penses of the office to be borne by the THE Report of the Commissioners of but the fact remains that while this country successful inventions. Considering that Patents for last year has been recently is the seat of all kinds of mechanical the amount of protection afforded to a issued, and in view of possible legislation industries, and needs, and can afford to pay patentee consists merely in giving him a next year contains some statements which for, every possible improvement, native in- primâ-facie right to the invention described are worthy of more than passing notice. vention does not progress as it should. To in his specification, for the technical accuThe number of applications for patents what cause is such a state of things to be racy of which document he or his agent is deposited at the office during the year was attributed? One would have expected the alone responsible, all the legal formalities 4,949, or 120 fewer than in 1876, a falling-off Commissioners to have taken a more lively required in granting a patent might surely which is probably due as much to the interest in the institution over which they be done for less than £25, and, remembering scarcity of money as to the decrease of rule than is exhibited by the mere collec- that up to last year no fewer than 104,991 invention. The ominous announcement, tion of dry statistics annually presented for specifications have been left at the office "not proceeded with," has been seen on a the edification of all who choose to read with stamps, the funds in hand must have very large number of specifications dated in them. The object of patents is to foster reached such an amount that the cost of 1877, and a still larger percentage will pro- and encourage invention, which is practi- taking out a patent might be safely reduced bably be found in 1878. No doubt many of cally only another name for the commercial without any fear of the Government being these were absurd or useless inventions, for and industrial welfare of the country; but compelled to subsidise the "department the Patent-office is more frequently visited for any suggestion how that may be secured from the national purse. Previous to 1852 by simpletons than by really clever men; and improved we should look in vain in this the number of specifications enrolled was but it is impossible to get away from the report. Of the facts we have specially men- less than 14,000, but in the last quarter of fact that the high fees charged for such tioned there is not a word in the report, a century the number has increased to protection as the "Letters" afford, practi- which contains a bare record of the business 105,000, and, taking only 10 per cent. as the cally prevent the growth of real invention. done and of the arrangements made for the proportion of valuable patents, it is worth When we remember that a man who, in convenience and assistance of the public while to consider whether it is not time to accordance with the law, deposits a full and would-be patentees. We are told that still "further encourage inventions in the account of his specification with the Com- the Commissioners, feeling the necessity useful arts" by making a patent more easy missioners, and receives in return only a for the revision and consolidation of the to obtain. piece of parchment with a large medal of alphabetical and subject-matter indices, very indifferent sealing-wax, it must be have decided on forming a special index confessed that £40 is a large sum to pay staff for the purpose, and that arrangefor it. The stamps, it is true, do not cost ments of specifications are prepared and 40, but there are few agents who will published in classes; we are also informed are none the worse that they come to undertake to complete a patent of the that copies of the Commissioners' publica- us all the way from America, and we welsimplest kind for a much smaller sum than tions, including about 100,000 specifications come this popular brochure from the pen of that, and even if the inventor does the work of distinct patents, may be purchased at Dr. Angell, professor of ophthalmology in himself the time occupied in searching, in the sale department in Cursitor-street. Boston University, as a useful book of preparing the drawings, and in carefully These announcements are made in such a much value to parents and guardians at a wording the specification, to say nothing of manner that the public is vaguely conscious time when defective sight is becoming the copies he is required to furnish, will, at of having been higbly favoured in some almost the normal condition amongst the a moderate sum per hour, amount to cer- unknown way, whereas in any properly. youth of our generation. Before we can tainly a moiety of the difference. The regulated Patent-office everything that could take proper care of the eyes we must know number of men who have £40 to spare for assist the inventor would be done as a mat- something of their construction, and be what is in many cases a speculation must ter of State policy, and the preparation of able to interpret accurately the meaning of be limited, and inany of those who are the indices and abridgments would be regarded the effects experienced, and trace them to possessors of sufficient funds have possibly as one of the primary duties of the office. their cause. We can neither afford to give little incentive to invent. Hence invention Patent agents and would-be patentees have up the use of our eyes because they ache, lags behind in this country, and has nearly had reason during recent years to appre- nor to disregard ominous symptoms, lest left us altogether, to flourish in the United ciate the benefits conferred by the excellent we run the risk of impairing the sight. We The number of applications re- indices and abridgments that have been wish to use our eyes, to preserve our sight, ceived in 1852 was 1,211, and the new Act prepared since the alteration in the law, and to prevent avoidable disease. having come into operation in that year the and if they were only kept closer up to date more general symptoms of changes from number steadily increased until in 1876 it nothing more could be desired, for the the normal state of the eye are those which reached 5,069. These figures, however, by librarian and his assistants are always gradually increase until they reach the no means represent British progress in ready and willing to help the stranger in stage of confirmed short or long sight. invention, for during recent years a very his search. The work of consolidating the The latter very frequently comes on with large number-a constantly-increasing per- indices and re-writing abridgments of the age; but the former is the more common centage, in fact are "communications from older specifications is, no doubt, a heavy defect, and under certain circumstances is abroad," mostly the inventions of American labour, but, in spite of the large salaries symptomatic of disease. In long sight, to citizens or persons settled in the United paid to the law officers, there is an enor- describe the defects popularly, we may say States. Thus, taking one week at random mous accumulated fund derived from the that the eyeball is too flat-that is, its verin last month, we found that out of 107 fees paid by inventors-a fund so large that tical diameter is greater than its horizontal applications no fewer than 36 were made by the expense of preparing the indices will diameter, and the rays of light focus at a or on behalf of persons resident abroad; or, scarcely reduce it in any perceptible manner. point beyond the retina. The optical in other words, one-third of the prospective But, although these indices and abridg- remedy is convex glasses, which should, patents during that period were for the ments may facilitate "searches," they will however, be used only under the advice of inventions of foreigners. British patentees do little to encourage invention-and that the oculist, who will determine the degree no doubt apply for patents in the United is the object of a Patent Law, without of convexity required. The focussing or States, France, and Germany, and help to which there would be no necessity for accommodative power of the eye, which deswell the lists in those countries; but, Commissioners. Failing, then, any digest pends upon the action of a muscle, in although the fees are comparatively low in of the statistics, we must be contented with changing the degree of convexity of the the United States, we doubt whether the the bare figures and the tables, from which lens is affected by many causes, the most foreign applications represent one-third of we learn that only about 29 per cent. of the potent of which is the manner of using the the total number received at Washington. patents granted from 1852 to 1870 paid the eyes-in other words, the habits of the inIt is not improbable that the majority of third year's stamp duty of £50, which con- dividual. In the case of children an almost the 36 foreign applications above mentioned tinues the "letters" in force until the end were complete specifications, for which the of the seventh year, when £100 becomes VOL. XXVIII-NO. 707.

States.

The

The Sight and How to Preserve it. By H. C. ANGELL, M.D. London: Hardwicke and Bogue,

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BOUGHT PORTIONS, MACHINERY, &c. Inc. THEIR VENDORS AND PURCHASE, For PRICES, see that Head (own Depart.)

r. Among the first questions asked by the Organ-builder not overburdened with capital are,-what can I make, and what must I buy? To meet these I have devoted one entire De

tions or other matters connected, which will

continuous use of the eyes over short dis- tive and irritable under the action of light tances, as in reading, necessitating as it as to be practically useless. It should be does the action of the accommodative remembered that in any defect of the eye it power, the convergence of the two eyes, the is most important to take advice early, for movement of the pupil and adjacent tis- while recent cases of mere weakness are sues, and a forward movement of the whole readily curable, severe cases are only cured eyeball, is supposed to promote the bulging with difficulty. The tendency to short-sight on tissues which at that age are peculiarly young is symptomatic of some lesion which demand direct money outlay. I have given, of the eye at the back by muscular pressure is progressive, and when occurring in the partment to the consideration of Bought Por. yielding and liable to take permanently may involve the integrity of the eye, and that form which they are compelled to unless the patient is prevented from using assume most frequently. The eyeball his eyes, delay is dangerous, for the defect having thus become longer in its hori- will increase, and if disease is at the root zontal than its vertical diameter, the rays of the evil, irremediable mischief may be of light focus before reaching the retina, wrought by postponing the visit to the and objects appear indistinct and hazy oculist. Dr. Angell gives hints upon other unless very near the eye. The optical defects of the eyes, such as astigmatism, and, remedy is the use of concave glasses, which useful type-tests for ascertaining the power in the case of adults, may be resorted to of vision, with notes on the common acciunder the advice of the oculist with safety; dents to which the eye is liable. but in the case of children it is advisable to try other remedies before employing the

first, a complete List of all those portions, &c., which can at any time require to be directly purchased; following these are Remarks on each. Next is given a list of Portions, with Vendors, &c.; and, finally, the actual Addresses of latter. A few hints as to amount and method of purchase are introduced where required. The order being in all cases Alphabetical, the adding of Figures and Letters to the said List has not been judged necessary.

s. It must be understood that nothing that is not in the List next following can at any time require to be directly bought, the Builder's own

TREATISE ON ITS MANUFACTURE, making. With regard to the Names given, this

PROCURAL, AND LODGMENT.*

BY JOHN WATSON WARMAN,
Associate of the College of Organists, London.

MANUFACTURE.

optician. Dr. Angell says that myopia in THE ORGAN: A COMPREHENSIVE Shop furnishing all requisite conveniences for children is almost invariably a disease as well as an optical defect. The elongation of the eyeball is at the back, and as the outer or protective coat of the eye is stretched, the two inner tissues (vascular and nervous coats) are unnaturally distended also. The inner tissues do not bear PART I.-GENERAL TREATMENT IN the parties instanced the author has had direct this distension well: they become thinned, congested, inflamed, degenerated, and finally are partially lost over a limited portion of the interior of the eye near the entrance of the optic nerve. When we look into such eyes with the ophthalmoscope, we see at this diseased part, not the retina and the middle or vascular coat, as in the healthy eye, but the outer covering, the glistening white-of-the-eye shining through those attenuated tissues. Where the ophthalmoscope discloses such a condition the first and best thing to do, says Dr. Angell, is to stop all reading, and as far as possible all use of the eyes for near objects, while encouraging the patient in his attempts to see distant objects. With this view rambles over hills, which give views of the country for miles around, are doubly useful, for they help to improve the general health, which is often much below par in the myopic. Improvement in sight will be found to be very rapid, and will continue for perhaps six months or a year, when it will cease as far as mere ability to see at a distance is concerned. The oculist should then be consulted, and if necessary proper glasses obtained, when the studies may be recommenced practically with safety.

obviously is a rather delicate matter, and it must be distinctly understood that in no case (unless it be so directly specified) is any name put forward as being pre-eminent, or even superior among others. With some of dealings, and, in such case, the insertion of the name is, of course, a sufficient guarantee of j. No. O. 2 is met by care in the proper selection satisfaction so far as he is concerned; but the of Section to which to apply. Thus in greater part of the addresses have been comthe Pedale all notes are practically doubled-piled from advertisements, the only guide in that is, all for which there are Pipes; same such cases usually being the general style, and thing is the case to a great extent on Solo. the prices attached: and the author feels it most k. No. 3 is included in preceding, or largely candid to observe that in very few branches has so: it will, for instance, be very certain his actual executive experience been sufficient that the cost of, say, two octaves of Pedal to enable him to put his finger upon the parti action, and the few top Pipes necessary will be cular Vendor giving most value for money, nothing to the cost of, say, a complete 8ft. even supposing such to exist. Violoncello; and if we take, instead, the borrowing of a 32 from a 16 the difference will be still greater, and here we are always on safe ground: when the Borrowing takes the form of an Octave Coupler to several Stops the gain is obviously immense.

1. The following considerations, then, should be carefully attended to:

m. First refer to rules previously laid down (in Extent and Method 23, j; and on).

n. The Touch must not be perilled; rememremains the same (that is, it is no greater than ber that, although the total of Pallet surface if the Pipes obtained were present as actual independent Stops), yet there will, if the Borrowing be by Action, be the friction of the additional

movement.

0. The Pedale is always the Section to which Borrowing best applies; and it is as well to repeat here what has been already said-viz., that the Expedient is on this Clavier of such value that, except in very peculiar cases, or very costly Instruments, it is simply unwise not to make use of the effective assistance it affords, either by Borrowing, properly so termed, or by an Octave-movement Coupler.

p. For reasons why latter, although not coming strictly under the Head of BORROWING, has been so freely dwelt upon here, see a few pages back (28, h.) The advantages of Borrowing as compared with a simple Coupler of this kind will be directly seen in the maintenance of the additions as individual Stops; the disadvantages will be as readily perceived in that with the Coupler one Movement Stops; thus increasing the effect in proportion or Action may add almost any desired number of

Simple weak sight, which comes upon us in middle life, especially if we are engaged in occupations or indulge in habits which require the constant use of the eyes, is due principally to an overworked, sensitive condition of the muscles of accommodation and convergence-a condition which frequently exists in cases of long sight, for as an oversighted eye must continually exert itself at all distances to focus rays of light, it is almost certain to overuse its accommodative power. Dr. Angell gives the rules to be observed by those who suffer from weak sight, and expressly cautions us not to read in trains or omnibuses, because the oscillations of the vehicle occasion fatigue to the accommodation muscles of the eye, owing to the exertion of keeping the focus and the proper amount of convergence. If the weakness of sight does not improve by resting the eyes, convex q. As a wind-up I think it may be confidently glasses will be necessary, and for the bene- laid down that by Borrowing we may save Pipes, fit of those who cannot consult an oculist, but not Room; exceptions there may often be, Dr. Angell says that glasses of 48in. focus as in the Pedale, but, as a broad rule, this may or thereabouts should be obtained, and used be confidently accepted. By bearing it carefully in mind, and paying regard to the more only in reading, sewing, and occupations detailed directions I have ventured to lay down, requiring similarly close application of the I have little doubt that sensible relief as reeye to the work. As soon as the eye tires, gards funds will be obtained; and this without the glasses must be removed. If no steps sacrificing the real effectiveness of the Instruare taken to provide a remedy for weak ment. sight as soon as it commences, there is a danger that the eyes may become so sensi

to the amount of mechanism.

All rights reserved.

t. Bear particularly in mind that the Patents only go as far as end of 1875; and that after that date, and indeed in all important cases, it will be desirable to go to the Patent-office itself.

*** LIST.

u. Baize.
Basis. See Joist-frame.
Bellows
Benches
Blowing-action
Bought Machinery and
Tools. See Machi-
nery and Tools.
Building-frame.
Carpet-thread.

Joist-frame.
Key-action. See Touch-

action.
Key-boards. See Ma
nual and Pedal-
board.
Key-warmer.
Kid. See Leather.
Lamb. See Leather.
Lead.

Case; inc. Design. For Leaf-turning Appli

Decoration see that
Head.

Claviers. See Manual

and Pedal-board.

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ances.

Leather; inc. Kid and
Lamb.
Lithographing.
Liquid Coatings; inc.
Staining.
Machinery, Manufac
turing; Important,
including Motors.
Machinery, Simple.
Manuals.
Materials. See Baize,
Cloth, Felt, Glae,
India-rubber, Lead,
Leather, Paper, Bod,
Tin, Wire,
Wood.
Measures. See Rules.
Mechanical Extras.
Models.
Motors. See Machi-

and

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Draw-action.
Draw-action, Electric.
Draw-action, Pneuma.
Felt; inc. Felt Drugget.
Paper;
Paper.
Glue-heating Apprtus.
Green-baize. See Baize. Patents.
Gauges for measuring Pedal-board.

Glue.

with.

Heating Apparatus.

See Warming.
Ironmongery, General.
India-rubber.
Inventions.See Patents.

inc.

Brown

Pipes, Metal. ForVoic ing see that Head. Pipes, Reed. For Tun ing appliances * Tuning. ForVoicing see that Head.

Pipes, Wood. ForVoic- Timber. ing see that Head.

Platform.

Pneumatic Buttons.
Pneumatic Lever.
Pneumatic Piston. See
Pneumatic Button.
Registers, Particular.
Rod. See Wire.

stuffs. Tin.

See Wood- here will usually be confined to Centers, Tugs
(when of metal), movable Handle-fittings,
Spindle, or other suitable work for Blowing.

Tools and Appliances
Bought. For Gauges,
Rules, and Tuning

Tools see own Heads.

Tool-chest.
Touch-action,

mon.

Com

Touch-action, Electric.

Rules for measuring
with.
Scales.
Touch-action, Levers.
Screws; inc.Screw-eyes Touch-action, Pneu-
and Shanks.
matic. See Pneu-
matic Lever.
Tow.

Seat

Shop

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All just said with respect to Foot-blower applies
equally here.

THE "SUN" GAS MACHINE AND
LAMP.

MANY attempts have been made to utilise the light hydrocarbons in the production of e. Winch Blower. Here the skilled Black- an air-gas capable of being safely consumed in smith must at once be employed for the Shaft, houses, and private persons have often endeaWheel, and Winch itself; the Rods may always voured to improve the illuminating power of be of wood. If no workmen near sufficiently coal-gas by passing it through a simple carskilful, go to Engineer, as previously said buretter, in which it is brought into contact (31, x). If Friction-wheels be used, the latter with benzoline in a finely divided state, or in person may be considered indispensable, as then, remember, lathe-work is involved.

f. Gas Engine. This, of course, must be bought; for the Crank-Shaft required, see preceding; the general fitting up, fixing, &c., may Tubing. See Draw- often be done by ordinary workmen.

Tremulant.

action.

g. Hydraulic Engine. This, too, must be Tuning; inc. Tools and bought out and out; no Crank-Shaft being necessary, the local Blacksmith may often do the requisite fittings.

Stops, Particular. See
Registers, Particu- Appliances.
Voicing.

lar.

Swell-box.

Tell-tale

Warming.

Wire and Rod.

Thread. See Carpet- Wood-stuffs. thread.

*** REMARKS.

h. Steam Engine. For this see Machinery, Manufacturing (31, x; and on).

i. BUILDING-FRAME. This will always be made at home; Bolts will be purchased; also perfectly for latter.

"GENERAL HOUSES. See VENDORS AND PUR- Runners, if of metal, but Hard wood answers CHASE, (35, s. and 37, t.)

**PORTIONAL.

V. BAIZE. The ordinary kind can always be easily obtained at the Drapers; the thick variety can only be got at special Houses. W. BASIS. See joist-frame (31, o.).

I. BELLOWS. The Organ-builder should, of course, by rights make his own Bellows, but as these are rather ticklish to construct well without experience, and impossible to make quickly without considerable practice, and as any defect here will ruin the Instrument, and moreover (owing to their being very much of a pattern in most Organs), they can be purchased with tolerable facility, the author would strongly advise purchase in all doubtful cases. y. Take care to specify Inverted Rib, Feeder drop, total size, ratio of Feeder size to latter, general design, number of Feeders, width of Ribs, number and form of Valves, and access to Interior: also materials and amount of leathering. For Leather and Tell-tale see those Heads (31, s., and 33, p.) For Poisoning of Leather apply to any intelligent chemist. Guidework of iron can easily be made at home, all required being a Bear, or a Punch and Bolster; but, if preferred, any intelligent smith will make. Weights, if of Iron, will generally be bought, as best cast; but Stone will serve, though not so well, as it is liable to break, also absorb moisture and become heavier, also takes more room. If Weights hung from springs better purchase latter, but this arrangement has been patented, so not at present accessible easily; its practical value, however, is too slight to be of any serious consequence.

however,

Z. BENCHES. It will not, in a general way, be worth while to purchase Benches, as they are so easily made; considering, moreover, that for Organ-work special forms and lengths of bench are required. The Screw may, and should, be purchased: it will be neither worth while to go to the expense of a Tap of such large size, nor, as a rule, to give an order to the turner, for the Screw and its Socket can easily be bought ready-made, most large ironmongers keep them; if not, the tool shop will furnish. The Screw-stop will also be purchased. [30. a.] BLOWING-ACTION. The extent to which outsiders will have to be employed for this work depends partly on circumstances, and partly on the nature of the Action itself. It will be best, therefore, to give each variety separately, so far as required.

b. Catgut best purchased of regular House. C. Foot-blower. If, as is generally the case, Ironwork is used, the Smith must of

course be employed; the most required, how

ever, will be the T-spindle and the Elbowed Pedal, both of which can generally be accurately made by any ordinarily intelligent Blackmith. If anything more exact than this is demanded apply to a working Engineer; for these see Machinery Manufacturing (31, x.). Have accurate Wood Models where necessary.

(To be continued.)

MEASUREMENT OF THE INTENSITY
OF SOUND.

To

measure sounds of different strength, M. Schafünth many years ago constructed a phonometer, in which small balls were allowed to fall from an accurately measurable height on a horizontal glass table; and by alteration of the depth of fall, and the weight of the ball, different intensities of sound could be produced. He came to the conclusion that the intensities of sound are proportional to the weight of the balls and the square root of the height, or to the velocity the balls had at striking. In opposition to this, M. Fechner contended that the case has to do only with the vis viva of the falling body, which is proportional to the square of the velocity, and so to the height of the fall; consequently this value is sufficient.

a state of vapour. The results have not often been of so satisfactory a nature as to encourage any widespread use of the more volatile products of petroleum, but the abundant supplies of petroleum naphthas in the United States gave an incentive to invention, and after soine years of trial we find that what is known as the "Sun Automatic Gas Machine" has at last arrived at what may be regarded as a very near approach to perfection. Originally invented, we believe, by Captain McEvoy, it has be not merely the best, but the only machine been improved by degrees until it is claimed to that will make a really useful air-gas. The hydrocarbon used is known commercially as gasoline, petroleum spirit, petroleum naphtha, &c.; it has a specific gravity varying between 61 and 65, and boils at temperatures ranging between 80 and 126° Fahr., and it is not unlikely that some failures may be attributed to the fact that mixed spirit has been employed, the lighter portions of which burnt with а brilliant flame while they lasted, but in evaporating effectually prevented the remainder and the greater bulk of the oil assuming the condition in which it can be taken up by air. Owing to the absorption of heat in the process of vaporisation the gas must always be slightly colder than the surrounding atmosphere, while it reduces the temperature of the still liquid gasoline until it no longer gives off vapour sufficient to charge the air with illuminating materials. To apply beat is to go to the opposite extreme, for if the vapour of a hydrocarbon were obtained at a temperature sensibly higher than that of the atmosphere the air-gas so produced would be liable to condensation in the pipes, and another failure would be the result. We will endeavour to explain how the difficulties have been surmounted by the Sun-Lighting and Heating In experiments which M. Vierordt recently Company. Referring to Fig. 1, which repremade on conduction of sound, he followed at sents a 100-light machine, it will be seen that first the mode of reckoning of M. Fechner, but the cylindrical portion, when half filled, will found so many contradictions that he deter- contain a very large quantity of gasoline commined to undertake an experimental investiga-pared with the gas-making capabilities of the tion of the two reckonings. For sound-giving machine. By this arrangement the effects of plate, he employed slate or metal plates, which evaporation in reducing the temperature are lay immediately on the table; and for falling kept at a minimum, for it is obvious that if one balls lead shot, which offered the advantage of gallon is vapourised it will have more effect upon, remaining on the plate after they struck. A say, three than upon thirty. In the Sun autosingle experiment proved decisive. M. Vierordt matic machine the cylinder or body is divided let one ball of 7mg. weight fall 116 2mm. on a transversely into two tanks, each surmounted. slate plate, while the space of fall of a second, as is seen in the figure, by a cone-topped both sensations of sound equally strong. Ac- level of the gasoline is kept as nearly as possible 36.5m. in weight, was 43mm., and he found chamber. In the tank nearest the weight the cording to M. Fechner's mode of reckoning, constant by means of a bucket wheel, which the mass (m) into the height (r) is in the first draws the gasoline from one tank and supplies 157. The it to the other, to make up for that which is evaporated and carried away by the air. The two tanks may be named the wheelchamber and the gas-holder respectively. In the former the gas line is kept up to a constant level, and a meter-wheel, the axis of which is below the surface, is slowly revolved, presenting to the air drawn in by the motion a large area of metal wetted with gasoline. The air enters by the cone furthest from the weight, and passing through the meter-wheel or blower enters the gas-holder or reservoir; the latter being filled, the air-gas finds its way up to the regulator or governor contained in the cylindrical top of the wheel-chamber, and thence by the outlet shown to the service pipes. When wound up the machine will run for about eight hours, supplying 100 lights, but in the event of its being necessary to rewind, the

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Such comparisons M. Vierordt made under various conditions of experiment, with great differences in strength of sound, and using plates with various capabilities of vibration, which gave either tones or noise; further, he listened for the sound either through the air, or with the aid of a wooden rod placed on the vibrating plate, and the upper end pressed against the ear; and in all cases, with different weights and heights, the equal products, mc, gave equally strong sensations, not the equal products, mc2.

The acoustic measure of strength of sound, with equal falling weight, is thus given, he concludes, not by the square of the velocity, but simply by the velocity which the falling weight has in the moment of its impingement on the plate. The simple velocity, however, is proportional to the square root of the height

d. Hand Lever Blower. The Bought portions of fallı

holder or reservoir contains sufficient gas to keep the burners going until the blower can be re-started. The smaller machines instead of a reservoir have an ingeniously-contrived arrangement, by which while winding the chain with one hand the motion of the meter-wheel is kept up by the other. Where a suppl. of water at a pressure of 181b. per sq. in. can be obtained a little turbine is attached to the machine in

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