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present at one moment than when uniform combustion goes on, which involves a lower initial temperature; and the damp and water of composition has also a stronger influence, being more quickly expelled, along with the hydrocarbon. This explains why the admission of air above the fuel frequently fails in preventing smoke, and generally entails loss of fuel. The only remedy is uniform and constant evolution of gas and combustion of cinder; with uniform draught, and the other conditions already referred to.

Where uniform evolution and combustion cannot be attained, probably the next best plan is that proposed by Prideaux,—to admit a variable quantity of air above, to suit the variable evolution of gascous matter.

In closing our remarks, it is evident that we have left untouched two very important heads of inquiry. First, We have carefully abstained from entering upon those practical details as to construction and size of furnace, &c., which the principles laid down have suggested. This has been done, from a conviction that much more depends on the regulation of draught, on depth of fuel, and especially on the position of the furnace, relative to the absorbing surface, &c., than on mere points of construction. For, however complete our arrangements may otherwise be, fuel will be wasted where draught is excessive, and smoke will be produced, more or less, where the flame, before it becomes converted into invisible gaseous matter, is allowed to touch a boiler-plate or other metallic conductor. In the second place, although we have assumed draught as capable of being calculated, and found it to be so, we have not entered on the subject. But the pneumatic laws which regulate the motion of gaseous currents are as definite as those which concern the phenomena of combustion, or the performance of the steam-engine. To those who object to the use of thermometers or pyrometers for initial and terminal temperatures, scales for registering area of damper, and gauges for force of draught, we would say,-look to the boiler, for the working of which the furnace is constructed, and the fuel consumed. Probably it is supplied with one or more gauges to indicate pressure, with gauge or float, to indicate depth of water, with safety-valve and fusible plug to prevent explosion,

with atmospheric valve to prevent collapse. Why all these? They are required. The same may be said with equal truth of those appliances in connection with the furnace, to which we refer. If the fireman has to watch the pressure of steam, and the depth of water, why not the area of the damper, the force of draught, and the weight of fuel. Towards such a system of operation, the present paper may be, perhaps, received by those to whom the subject is important, as a slight contribution.

Notes on Californian Trees. By ANDREW MURRAY, F.R.S.E. PART II. (Plates VI., VII., VIII., IX.)

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The history of this long-lived tree has been so fully detailed by the various authors who have noticed it, and more particularly by Dr Seemann, so recently as March last, in the "Annals and Magazine of Natural History," that I should not have thought of including it as one of the subjects of my notes, were it not for the sake of some photographs of the tree sent NEW SERIES.-VOL. XI. NO. II.-APRIL 1860.

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me by my brother, copies of which will, I feel sure, be acceptable to the public.

It is so far well that the possession of these photographs should have in a measure constrained me to include a notice of this tree in my list, as most certainly notes on Californian trees, without any notice of the Wellingtonia, would have been as bad as "Hamlet with the part of Hamlet omitted." But I have little new to say regarding it, and I only offer, as a pendant to the sketches I have given, a short resumé of what has been already published by others, and most of which has been collected by Dr Seemann, to whom I offer my acknowledgments for the use I have made of his able paper.

The tree is said to have been first seen by the unfortunate Douglas in his Californian explorations; but this has now been shown to be a mistake. The route by which he travelled is perfectly known, and he never came within a hundred and twenty miles of any of the known examples of Wellingtonia. What he saw was Sequoia sempervirens, as may be otherwise inferred from the terms in which he speaks of it. The real Wellingtonia was first discovered by Mr Lobb, and introduced into this country in 1853, and described by Dr Lindley in the "Gardener's Chronicle" in that year. An ancient Californian tradition, of nearly ten years' existence, ascribes its discovery to a Mr J. M. Wooster, as one of the trees in the Mammoth Grove bears on its bark the inscription of "J. M. Wooster, Ju. 1850." Of course it had been discovered in a literal sense long previously by the Californian aborigines; but as priority of discovery depends upon priority of publication, they must give way; and as Mr Wooster's publication, at the best, can only be looked upon as a manuscript notice, we must, under the rules which regulate priority in such matters, hail Mr Lobb as first discoverer, although admittedly he himself was directed to it by general rumour current among the European settlers.

Dr Lindley is still more undeniably the first describer, and the name given by him to the tree (Wellingtonia gigantea) has of course precedence over all others. Notwithstanding this, the Americans made a strong effort to change the name into one bearing reference to Washington. As Dr Seemann tells us, "they even commenced in their newspapers an agitation against the adoption of the name Wellingtonia, quite

ignoring that the savans of their country bow to the same code of scientific laws which govern the conduct of their European brethren, and that no amount of popular clamour could cause the right of priority here at stake to be set aside. When, therefore," says he, "Dr Winslow exhorted his countrymen in grandiloquent language to call the mammoth tree, if it be a Taxodium, T. Washingtonium; if a new genus, Washingtonia Californica; he simply proclaimed to all the world that he knew nothing whatever of the laws governing systematic botany." Perhaps the reader may like to see a specimen of the style under cover of which Dr Winslow proposed to effect this act of appropriation. It reads more like a speech concocted by Dickens for Mr Jefferson Brick than a real true bona fide speech. But I beg to assure them the article is genuine. It is as follows:

"The name that has been applied to this tree by Professor Lindley, an English botanist, is Wellingtonia gigantea. By him it is declared to be so much unlike other coniferæ, as not only to be a new species, but to require description as a new genus. Other botanists of eminence think differently. To this, however, he has seen fit to apply the name of an English hero, a step indicating as much personal arrogance or weakness as scientific indelicacy; for it must have been a prominent idea in the mind of that person that American naturalists would regard with surprise and reluctance the application of a British name, however meritoriously honoured, when a name so worthy of immortal honour and renown as that of Washington would strike the mind of the world as far more suitable to the most gigantic and remarkable vegetable wonder indigenous to a country where his name is the most distinguished ornament. As he and his generation declared themselves independent of all English rule and political dictation, so American naturalists must in this case express their respectful dissent from all British scientific stamp acts. If the big tree be a Taxodium, let it be called now and for ever Taxodium Washingtonium. If it should be properly ranked as a new genus, then let it be called to the end of time Washingtonia Californica. The generic name indicates unparalleled greatness and grandeur; its specific name, the only locality in the world where it is found. No names can be

more appropriate; and if it be in accordance with the views of American botanists, I trust the scientific honour of our country may be vindicated from foreign indelicacy by boldly discarding the name now applied to it, and by affixing to it that of the immortal man whose memory we all love and honour, and teach our children to adore. Under any and all circumstances, however, whether of perpetuity or extinction, the name of Wellington should be discarded, and that of Washington attached to it and transmitted to the schools of future ages."

Does the reader concur with Dr Seemann in thinking that all that this gentleman, who is so sensitively alive to the feelings of delicacy, shows in this oration, is ignorance of the laws governing systematic botany? With great deference, it seems to me to show an ignorance of something much more important-viz., ignorance of the first principles of common honesty. The appropriation in this instance would have been a double theft, first of the honour or right to his own appellation, which belongs to every sponsor; and next of the happy idea which led Dr Lindley to consecrate this grandest of trees to the grandest of our national heroes. As Messrs Sang and Co., nurserymen, Kirkcaldy, say, in an exceedingly neat and comprehensive account which they have published of the tree and its history, if the Americans want such a memorial for their great man, let them discover and describe their big trees for themselves. This attempt at appropriation, however, has failed. The better class of American botanists have repudiated it, and in a few years the name Washingtonia will have passed from the memories of men, except as a scientific, or rather unscientific, synonym.

Doubts, however, have been cast upon the distinctness of Wellingtonia as a genus, which, if well founded, might deprive us of that name. True, Dr Seemann, who is next in priority, has attempted to save it by condemning the specific name gigantea, as already preoccupied, and substituting Sequoia Wellingtonia for Wellingtonia gigantea; and his reasons for holding that the specific name gigantea has been already misapplied by Endlicher seem probable enough; but I trust we shall not require to settle this point. The genus seems perfectly goodas good, indeed, as any genus in this difficult and closely allied

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