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and remain there ready to take it other method, which employs the back. The French Mathematicians measure of a pendulum, had, toge placed their little repeating circle at ther with the preceding, been praca short distance off, 'in a shed which tised on all the points of the arc. As the administration of marine had di- account had last year been given, ofa rected to be constructed for them. tour made in England, Scotland, and There, owing to a continuatio... of the Shetland Isles, to carry the appagood weather, so little time was left ratus of the pendulum over the whole for relaxation, that all the observa. extent of the English arc. The English tions were finished in fifteen days; government, which had favoured this and when completed, were found to operation, naturally desired that it agree in a surprising manner, if the should be executed, io like manger, different nature of the processes be by an observer of their own nation. considered; and what is still more for- Captain Kater, member of the Royal tunate, they were found also to ac. Society London, an experimentalist ! cord perfectly with those which M. singularly exact, and author of an ex. Delambre had formerly made in the cellent memoir on the length of the same place, at the commencement of pendulum vibrating seconds in the his operations ; whence results the latitude of London, was deputed for double assurance, that the arcs of this purpose. With much precaution, France and England are thus per. he conveyed to Edinburgh and the fectly connected with each other; Shetland Islands, a solid pendulum, while the observations made on the of an invariable form, the diurnal rate other points of the two arcs, by simi- of which he had previously determislar processes, afford all the precision ed at London ; and the oscillations of which can be desired.

which he had also observed in these As it was expedient that the point different places. It is the same opera. of junction of the English and French tion which Capt. Freycinet was to exoperations might always be re-ascer. ecute, in his voyage round the world, tained, MM. Arago and Biot resol. with pendulums constructed under ved to erect some lasting monu- the direction of M. Arago. Capt. Kater ment. The city of Dunkirk freed was received at the Shetland Islands them from this care. A little marble by the same Mr Edmonstone who had column, surmounted with a spire, is received M. Biot with such obliging to be erected in this place, and a short hospitality two years before. inscription will record the object of made his observations in the same the operation, with the names of the place where M. Biot did, with the observers of the two countries. At same assistance and with the same acthe Shetland Isles, the extremity of commodations. The observations of the great arc has been marked in like Captain Kater have been found to manner, in the garden of Mr Edmon- accord in a remarkable degree with stone, by a little monument which he those of M. Biot, as was ascertained has caused to be erected in the place by mutual comparison. Having thus where the observations were made. the lengths of the pendulum mea. In Spain, in the isles called Balearic, sured by an uniform process upon the the southern extremity of the arc is same meridian from Formentera, the consecrated by a cross.

most southerly of the Balearic Isl. These operations refer to the first ands, to Unst, the most northerly of the methods by wl ich the figure of of the Shetland Islands, and not onthe earth may be determined. The ly in these two islands, and in a great

number of intermediate points, the geography, which assigns to each tribe flatness of the earth can, by these of plants their height, limits, and clilengths, be determined with great ex. mate. The terms alpine plants, plants actness. The amount resulting is of hot countries, plants of the sea. found to be exactly the same as that shore, are to be found in all landerived from the lunar inequalities, or guages, even in those of the most safrom the comparison of terrestrial de- vage nations on the banks of the Orogrees measured at very distant lati- noko, and prove that the attention tudes ; so that all these methols, so of men has been constantly fixed on different in their progress, so distinct the distribution of vegetables, and on in their processes, definitively ter- their connexion with the temperaminate in this one result--the flatness ture of the air, the elevation of the of the earth; namely, the excess of soil, and the nature of the ground the equatorial above the polar radius; which they inhabit. It does not rethe excess of the former above the quire much sagacity to observe, that latter amounting to a quantity inter: on the slope of the high mountains of mediate between giz and sto The Armenia, vegetables of a different ladifference of these extreme values, titude follow each in succession, like between which the truth lies, will the climates, superimposed, as it were, hardly give a hundred toises, more or upon each other. less, on the half of the axis which The vegetables, says M. Humboldt, passes through the poles of the earth; which cover the vast surface of the

and from the number and exactness globe, present, when we study their De of the diversified observations by natural classes or families, striking,

which this truth has been establish- differences in the distribution of their

ed, there can no longer be room for forms. On limiting them to the coun9% discussion on the subject.

tries in which the number of the species is exactly known, and by divid.

ing this number by that of the glu. Alexander Count Humboldt sub- maceæ, the leguminous plants, the mitted to the Institute a curious pa. Jabiated, and the compound, we find per, on the laws observed in the dis. numerical relations which form very iribution of vegetable forms over the regular series. We see certain forms globe. Botany, long confined to the become more common, from the description of the external forms of equator towards the pole, like the plants, and their artificial classifica. ferns, the glumaceæ, the ericeæ, tion, now presents several bra hes of and the rhododendra. Other forms, study, which place it more on a foot. on the contrary, increase from the ing with the other sciences. Such poles towards the equator, and may are the distribution of vegetables, ac. be considered in our hemisphere as cording to a natural method founded southern forms: such are the rubiaupon the whole part of their structure; ceæ, the malvaceæ, the euphorbiaceæ, their physiology, which displays their the leguminous, and the composite internal organization; their botanical plants. Finally, others attain their

* For the convenience of such of our readers as have not made descriptive botany a particu. lar study, we shall here subjoin the translation of the names of some of the most common plants which characteristise the tribes or families most frequently the subjects of discussion in Baron Humboldt's memoir : Junciæ (rushes ;) cyperacece (hard or moor grasses, cottongrass ;) gramineæ (corn, grasses ;) compositæ (dandelions, thistlęs, sunflower;) leguminusce or papilionaceæ (vetches, pease, clover ;) rubiacea (rennet, madder ;) cuphorbiaceæ (sunpurge, dog's mercury ;) labiala (mint, thyme, rosemary;) milvaceæ (mallows, hollyhock;)

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maximum even in the temperate zone, Lapland there are only 497 phanero. and diminish also towards the equa- gamous plants ; among which are 124 tor and the poles ; such are the la- glumaceæ, 58 composite, 14 legubiated plants, the amentaceæ, the minous, 23 amentaceous, &c. cruciferæ, and the umbelliferæ. The Mr Pursch bas made us acquaintgrasses form in England 1-12th, in ed with 2000 phanerogamous plants France 1-13th, in North America which grow between the parallels of 1-10th, of all the phanerogamous 35% and 44°; consequently, under plants. The glumaceæ form in Ger- mean annual temperatures of 16 and many!-7th, in France 1-8th, in North 7. The Flora of North America is America 1-8th, in New Holland, ac- a mixture of several Floras. The cording to the researches of Mr southern regions give it an abundance Brown, 1-8th, of the known phane- of malvaceæ and composite plants; rogamous plants. The composite the northern regions, colder than plants increase a little in the northern Europe, under the same parallel, furpart of the new continent ; for, ac. nish to this Flora abundance of rhodocording to the new Flora of Pursch, dendra, amentaceæ, and coniferæ. there is between the parallels of Geor- The caryophylleæ, the umbelliferæ, gia and Boston 1.6th, whereas in and the cruciferæ, are in general more Germany we find 1-8th, and in France rare in North America, than in the 1.7th, of the total number of the spe- temperate zone of the Old Continent. cies, with visible fructification. 'In These constant relations observed the whole temperate zone, the glu- on the surface of the globe, in the maceæ and the composite plants form plains from the equator to the pole, together nearly one-fourth of the are again traced in the midst of perphanerogamous plants; the gluma- petual snows on the summits of moun. ceæ, the compositæ, the cruciferæ, tains. We may admit, in general, and the leguminosä, together, nearly that on the Cordilleras of the torrid one-third. It results from these re. zone, the boreal forms become more searches, that the forms of organized frequent. It is thus that we see prebeings are in a mutual dependence; vail at Quito, on the summit of the and that the unity of nature is such, Andes, the ericeæ, the rhododenthat the forms are limited, the one dra, and the gramineous plants. after the other, according to constant On the contrary, the labiatæ, the rulaws easy of determination.

biaceæ, the malvaceæ, and the euThe number of vegetable species phorbiaceæ, then become as rare as described by botanists, or existing in they are in Lapland. But this ana. European herbals, extends to 44,000, logy is not supported in the ferns and of which 6000 are agamous. In this the composite plants. The latter a. number we had already included 3000 bound on the Andes, whereas the new phanerogamous species enume- foriner gradually disappear when they rated by M. Bonpland and myself. rise above 1800 fathoms in heighi. France, according to M. Decandolle, Thus the climate of the Andes repossesses 3645 phanerogamous plants, sembles that of northern Europe onof which 460 are glumaceæ, 490 com. ly with respect to the mean tempera. posite, and 230 leguminous, &c. In ture of the year. The repartition of

umbellifera (carrot, hemlock, chervil, caraway ;) cruciferæ (mustard, cresses, radish, turnip) The great mass of plants which cover the globe is divided by botanists into plan amous (those having visible flowers,) and cryptagamous, or agamous (ferns, lichens, mushrooms.)

heat into the different seasons is en mined, differ specifically from the tirely different, and powerfully influ- analogous species of the temperate ences the phenomena of vegetation. zone of the Old Continent.

It has been long known, and it is one of the most interesting results derived from the geography of animals, that no quadruped, no terrestrial bird, 1.- Report on the State of Hydraulic and, as appears from the researches Architecture in Great Britain; from of M. Latreille, almost no insect, is the Work of M. Dupin, by Messrs common to the equatorial regions of GERARD, ARAGO, & PRONY. the two worlds. "M. Cuvier is con. vinced, by precise inquiries, that this Military Ports.-The arsenal at rule applies even to reptiles. He Deptford is the least considerable of has ascertained, that the true boa all the military establishments. That constrictor is peculiar to America; at Woolwich is much more worthy of and that the boas of the Old Continent notice, as it is more spacious, and, were pytons. Among the plants, we by its position, more adapted for the must distinguish between the agama construction of large vessels of war. and the cotyledoneæ; and by consi- From 1789 to 1799, three millions dering the latter, between the mono- and a half of francs were expended cotyledons and the dicotyledons. on the construction of basins, depôts, There is no doubt that many of the and workshops, for masts of ships mosses and lichens are to be found at only. once in equinoctial America and in At Woolwich, M. Dupin observed Europe. But the case is not the same a shed sheltered by a roof, the ironwith the vascular agamæ as with the work of which was covered with agamæ of a cellular texture. The sheets of the same metal. He also ferns and the lycopodiaceæ do not describes a new forge, constructed follow the same laws with the mosses on the plan of Mr Rennie, and on a and the lichens. The former, in par- very large scale, the bellows and hamticular, exhibit very few species uni. mers of which are put in motion by versally to be found ; and the ex- three steam-engines. Anchors are amples cited are frequently doubtful. manufactured there, and all large It is absolutely false, although it has pieces of iron cast and hammered been often affirmed, that the ridges of which are necessary for the works of the Cordilleras of Peru, the climate of ports. which has some analogy with the cli- The arsenal of Sheerness offers mate of France or Sweden, produce si. works much more worthy of notice milar plants. The oaks, the pines, the than those at Woolwich. Built on a yews, the ranunculi, che rose-trees, swampy island formed by the conflux the alchemilla, the valerians, the stel- of the Thames and Medway, it was laria, the draba of the Peruvian and necessary, in the first instance, to Mexican Andes, have nearly the same close up a factitious ground with the physiognomy with the species of the carcases of old vessels sunk in the same genera of North America, Si- mud, side by side. A short time beria, or Europe. But all, these al- since government bought the half of pine plants of the Cordilleras, with the town, and have taken down the out excepting one among three or houses to enlarge the arsenal. They four thousand which we have exa- have also built along the Medway a magnificent quay of Cornwall granite, sents some new important hydraulic upon piles sunk forty-eight feet be. constructions. Tie old docks, which low the surface of the water. were in wood, are rebuilding op :

At these works, they were busily very large scale in Portland store. employed when M. Dupin saw them. The old wooden docks did not close He describes very minutely the dif- with gates on turning their hinges, ficulties they had to overcome, in but with three great wooden pannek, draining the water, driving the set at low water, and kept in their piles, and building under water, by places by solid stancheons. They means of the diving-bell. The working propose to enlarge the arsenal a of this bell is effected by geometrical Chatham very much : in fact they movements, parallel with three co. wish to double it, by taking advanordinate rectangular axle-trees, by tage of a spacious island formed be means of iron notched roads, and fore the old part by the conflux of wheeled notched carriages. It can be the Medway. The new part they conveyed to any part under water intend solely for the building of nex without its being necessary to see it. ships, and the other for re-fitting the

Behind the new quay at Sheerness old ones. Thus, in spite of the cothey have built depôts for masts and lossal grandeur of the English navy, docks, well worthy of notice. Ac- government aspire still higher; and, cording to the custom of the English, in the calm of peace, display more the masts are preserved under water. and more the essential elements of They are ranged in piles, on floors naval war. formed by beams horizontal and pa- The arsenal of Chatham contains a rallel with each other, in contiguous fine workshop of sawing, recently harbours. Double sluice.gates before established by Mr Brunel. It is built these harbours permit them to be full on an eminence. The woods for sas. at low as well as at high water, and ing arrive by a subterraneous canal, to be emptied at will; so that masts at the bottom of a well, which emp. may be taken away or carried there. ties itself near the workshop. The In fine, after the disposal of these pieces of wood are raised by a coun. masts, by separate parallel plans, you terpoise formed by the water proceedcan draw away or place any piece ing from the cooler of the steam-enyou wish, without being forced to gine, which puts the saws in motion. derange the others. The water is This water, generally lost, is at times drained from these docks by chain- useful. A frame, of very curious conpumps, put in action by a steam-en- struction, carrying a double crane, gine of fifty-horse power,

put in motion by the steam-engine, Vessels may enter at high tide ; but the universal agent of the sawing. except in pressing cases, they wait machine, ascends and descends upon until the tide is low, to drain off the a curved surface of 300 metres long, water. They begin by opening the and takes away from, and brings back, food-gates, which allow it to escape the pieces of wood from their respecfrom the docks, and then there is but tive piles to the workshop for saving. very little water to pump off. The arsenal at Chatham offers, more

These magnificent works, execut. over, several methods by which a ed in granite of Cornwall to be more great body of water is immediately durable, will be completed in ten conducted to any given point, to burst years, and cost ten millions of francs. upon a fire.

The arsenal of Chatham also pre- The arsenal at Portsmouth is the

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