picea.)

10 Poplar,.

11 Pear

136 628 49 699 6 312 44 989 135 881 49 395 6 351 48 254 135 690 49 113 6 443 44 444 133 953 49 196 6-217 44 587 133 951 48 839 6 360 44.801 133.472 49 432 6.069 44-499 133 340 48 902 6.267 44-831 133 251 49 356 6.075 44 569 133 229 48 602 6-375 44-023 133 139 48 824 6 276 44 900 132.543 48 669 6 272 45 059 132 312 48 533 6-301 45 166 132 088 49 311 5 964 44 725 130 834 48 184 6-277 45 539 128 478 49 838 5 352 44 810

The practical application of these results will be evident, if we consider that the quantities of oxygen absorbed from the atmosphere during the perfect combustion of each kind of wood, is the correct expression of the combustible value of the wood, since the quantity of heat given out during combustion is proportional to the quantities of oxygen taken up.

New Map of Central Asia.

A MAP of Central Asia, compiled by M. Klaproth, and based upon communications made by the missionaries at Pekin, has been presented to the Académie des Sciences, by M. Landresse. By adding all the facts that could be obtained from the most recent authorities, particularly those derived from Chinese writers, M. Klaproth has been able to determine the configuration of the surface of these immense countries.

Correct Notion of Steam-Engine
Horse-power.

WHEN engineers speak of a twenty-fivehorse engine, they mean one which would do the work of that number of horses constantly acting; but supposing that the same horses could work only eight hours in every twenty-four, there must be seventy-five horses, at least, kept to produce the effect of such an engine. The largest engine in Cornwall may, if worked to the full extent, be equal to, from a three-hundred to a three-hundred-and-fifty-horse power,and would, therefore, require a thousand horses to be kept to produce the same constant effect. In this way it has been said that an engine was of a thousandhorse-power, but this is not according to the usual computation.-Letter of J. Taylor, Esq.. to Dr. Buckland.

Combe.-Application of the Term.

THE term Combe, so common in the names of upland villages, is usually applied to that unwatered portion of a valley, which forms its continuation beyond, and above, the most elevated spring that issues into it; at this point, or spring-head, the Valley ends, and the Combe begins. The convenience of water and shelter which these springheads afford, have usually fixed the site of the highest villages that are planted round the margin of elevated plains. -BUCKLAND's Bridgewater Treatise.

1836.

Bottles, &c. sunk in the Sea.

CAPT. SMYTH found, on two trials, that the cylindrical air-tube, under the vane attached to Massey's Patent Log, collapsed, and was crushed quite flat, under a pressure of about three hundred fathoms. A claret-bottle, filled with air, and well corked, was burst before it descended four hundred fathoms. He also found that a bottle filled with fresh water, and corked, had the cork forced at about a hundred and eighty fathoms below the surface; in such cases, the fluid sent down is replaced by salt-water, and the cork, which had been forced in, is sometimes inverted.

Capt. Beaufort also informs me, that he has frequently sunk corked bottles

in the sea, more than a hundred fathoms deep, some of them empty, and others containing a fluid; the empty bottles were sometimes crushed, at other times the cork was forced in, and the bottle returned full of sea-water. The cork of the bottles containing a fluid was uniformly forced in, and the fluid exchanged for sea-water; the cork was always returned to the neck of the bottle, sometimes, but not always, in an inverted position."-BUCKLAND, Bridgewater Treatise, 1836.)

Suggested Sessional Journal of the

British Association.

Too much publicity cannot be given to the important investigations and undertakings which have been recommended, and for which funds have been provided, at the several sessions of the British Association, if any useful and valuable results are to be obtained from them. This publicity, it would seem, must principally depend upon the voluntary and friendly assistance of the periodical press, for, beyond the range of the General-committee-men present at the voting of the money, and who no doubt knew what they were voting it for, not the smallest effort has been made, as far as we (members) know, by the managers of the Association, to disseminate the information. One-sixth of this year has already run out, and we know individuals, selected as directors of these investigations, &c. and disposers of the funds, who are not yet acquainted with their appointment. The vital principle of the Association is voluntary exertion-scientific labour for the love of it; but how are the energies of the members and friends of the Association to be roused and directed, if the officers who possess the information do not distribute it? Suppose the reporters of the public press had not attended, and the copious accounts of the meeting had not been given by this Magazine, by the Athenæum, and other journals, how little would have been known of the proceedings of the Association up to this hour! We recommend the most unsparing expense to acquire, and extensively distribute, the earliest and most copious accounts of every transaction, suggestion, &c., of the Association as a body, and we submit to the consideration of the managing body, (if any such exists in the interval of the

meetings,) to deliberate upon the propriety of providing reporters for each Section,-for each meeting of the General· committee,-for every one of the Aggregate Meetings, that there may be obtained, and immediately printed, the most ample reports of each meeting, (even those of the Dinners should not be omitted.) Why not embody them in a morning publication, to begin a week before the meeting takes place with that preliminary information which every visiter has hitherto been distressed for, and to be continued not only during the days of meeting, but for as many days after as may bring up the arrears that unavoidably accrue? This may be entitled the "Journal of the Session," and from being prepared on the spot at the time of meeting, and under the revision of persons, in possession, from official position, of accurate and early information, it would be free from those errors and deficiencies which must happen to others who are not responsible for their accuracy, and cannot command admission to meetings, documents, &c. What grant of money which has been made, or ever can be made, would more effectually promote the great interests of the Association? What would more facilitate the acquisition and interchanges of information during the meeting, and prevent those eternal regrets of lost opportunities which fill the last day or two of the session? What could more promptly, and extensively, and satisfactorily, circulate to the distant friends of science, the gratifications, the advantages, and the acquisitions of those who are present? But, we believe, no grant, or, at most, a very small one, would be necessary. With proper management, a very lowpriced Journal might accomplish this great desideratum, and pay its own expenses. With this on our table, we could wait with more temper than we have done during the twelve months that the volume is in labour.

In the absence of such means, we shall continue to acquire, and insert all information in our power, which may appear to us to be necessary for the members, and promoters of scientific information not members, to be made acquainted with. Of this nature we conceive the items in the following list to be, but of which we have no means of being quite certain of the completeness or accuracy.

Nerves.

King.

Hodgkin, Roupell.

Adams, Carmichael,

25

Green, Macdonald,

O'Beirne, Smith.

Broughton, Cock,

Harpey.

Hallam,

Porter,

Sykes.

50

Philanthropic Deposit.

'I FEEL it to be a public duty, to make known an act of Mr. Buddle, which will entitle him to the gratitude of posterity, and has set an example which, if generally followed, will save the lives of thousands of unfortunate miners, that must otherwise perish for want of information, which can, at this time, be easily recorded for their preservation. This eminent Engineer and Coal Viewer has presented to the Natural History Society of Newcastle, copies of his most important plans and sections, accompanied by written documents, of the under-ground workings in the collieries near that town, in which all those spaces are carefully noted from whence the coal has been removed. The sudden irruption of water into a mine adjacent to such reservoirs, is occasionally attended with most cala

mitous and fatal results."-(See History of Fossil Fuel, the Collieries and Coal Trade, 1835, p. 249, &c.)

The dictates of humanity which prompt us to aid in the preservation of human life, no less than the economical view of rendering available, at a future time, the residuary portions of our beds of coal, which will not now repay the cost of extracting them, should induce all proprietors, and other persons connected with coal-mines, and especially engineers and coal-viewers, to leave to their successors a legacy, which will be to them precious, by preserving minute and exact records of the state of the coal in their respective districts. It can, however, scarcely be expected, that such measures will be generally and systematically adopted throughout the many coal-fields of this country, unless the subject be legislatively taken up by those official persons, whom it behoves,