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than the surrounding hills. You have heard much of the scenery, but I wish you had seen some of it, for no pencil has yet done justice to it. To mention one: conceive yourself on the top of the Choor mountain, nearly 13,000 feet above the level of the sea, a lofty ridge half way between the snowy range and the plains, high above every thing around. Imagine a glance to the north, or front, with an uninterrupted stretch of upwards of 90°! of snowy mountains, without a break, clear, white, and dazzling, starting up against a back-ground of deep-blue sky, so rich and intense, as you have never seen: conceive an ocean of mountain waves, running on from your feet to the snow, you looking down upon and overtoppiug all. Turn round to the rear or south, and you have another sea of hills, with the plains of Hindoostan beyond, stretching far 0!? into the distance, and traversed by here and there a streak of silver, marking the miniature course of the mighty J umna. Look to right and left, and you have a view of mountains, bounded only by the limits of vision: the huge masses of huddled granite about you forming a fine offset to the whole. I imagine thatas a panoramic mountain view, that of the Choor is not to be exceeded in any country, and it is but a sample of the rest. The only want is in lake scenery, and of this there is nothing worthy of the name.”
It had invariably been remarked by meteorologists that a rain-gauge, placed at an elevation, collected less rain than one situated on the surface of the ground, yet no satisfactory reason could be assigned for such a discrepancy. The British Association for the Advancement of Science determining to place the facts of the phenomenon on such a footing as to be afterwards capable of tolerably strict analysis, engaged Messrs. W. GRAY and J. PHILLIPS, to conduct a year's cxperiments on the top of the Cathedral at York, and the result was made the subject of a report by the latter to the meeting at Cambridge in 1833, which sets the matter at rest in a most satisfactory manner.
The site of the experiments was well selected, York being in the centre of 3 very extensive valley, and the Minster tower, elevated 200 feet from the ground, looks down upon an area of 1000 square miles, with no object of nature or art rising to within 100 feet of its summit.
One gauge of the simplest construction was attached to a pole, elevated nine feet above the battlements, 242 feet above the river ;—another was registered on the roof of the museum, 721} feet ;—and a third on the ground in the museum garden, at 29 feet above the river.
The gauges were 10 inches square, and could be easily read off to the l000th of an inch fall.
The report gives a tabular view of the whole rain of the year, but it will be suf. flcient here to notice the totals of the 12 months, which were as follows:
» Minster. Museum. Ground. Total Rain-fall in thelyear, 15'910 20'461 24'40I or deducting a snow storm in Feb. 15'715 20182 23785
Mr. PHILLIPS arranges the numerical results of the experiments, in relation to mean temperature, and the season of the year, so as to deduce the ratios of quantity at the several stations, in the following table : -_-‘-_---F--__-'—-—-—'——_'-——_'____—_I_
The first remark which occurs on the inspection of this table is that the ratio of diminution of rain for altitude of position is nearly constant. Mr. PHILLIPS shows that it is represented by a simple formula, depending on the square 1-001; of the height with one variable co-eflicient; or m \/ It : the diminution of rain at the given height.
Thus for the whole year (m being made = 2'29) for the Minster, m ‘/ It = ‘/ 212-8 X 2'29: 665, by observation 661, to 100, for the Museum, mj it : J 4315 x 2'29 = 84'9, by observation 853, to 100,
In like manner for the seven coldest months, (m = 2'88,) the ratios are found
by calculation, 58 81 100 by observation, 58'6 80'5 100 and for the seven warmest months, (m = 1'97,) the same quantities are found, by calculation, 71-3 87'0 100 by observation, 71'2 87'1 100
and so on, for the five-monthly periods of averages. For the shorter periods, the accordance is of course less striking, butit obtains even in single months, and the same formula is found to applyto Dr. HEBE annN’s experiments on Westminster Abbey, with a due variation in the co-eflicient m. Whence it is concluded that the relation to height is constant.
But it is evident that the values of the variable co-eflicient were very difi‘erent; that its maxima and minima, were, perhaps, not quite in the same periods of the year at Westminster as at York, and that the range of variation in its value is much less. From M. ARAGO’s determination of the relative quantities of rain falling on the observatory at Paris, and in the court below, the relative mean value ofm, at Paris = 1'24 ; while at Westminster, it is 4-23; and at York, 2'29, These discrepancies are discouraging, and will probably deprive the most exact local determinations of a general application. However, on account of the re.
markable regularity of the progress of monthly temperature at York, and some obvious relations between the quantity of rain collected, and the mean temperature of the period, some inferences unavoidably suggested themselves.
First. The diminution at the upper stations is greatest in the cold, and least in the warm seasons, and therefore the co-efficient is in some way inversely dependent on the temperature. Mr. PHILLIPS found the relation very nearly represented by the formula 2 m = a .€’+ a where a = the ascertained value of m for the whole year, t the mean temperature of ditto, and 1' that of the particular period.
Secondly. The relation between the values of m and the dryness of the air is inverse, whether expressed by the difference between the mean temperature and the dew point, or, as that is seldom known, by the mean range of daily temperature, which had been determined for York from a long series of observations by Mr. F. CHOLMELEY, to be as follows :
January range, . . 8'0 May,.. . . . . . . . . . . 19'7 September, . . . . . . 16-0
February——, .. .. .. 101 June, .. .. .. .. .. 201 October, ,. .. .. .. 11-8
March—, .. .. 131 July, .. .. .. .. .. 19'6 November, .. .... 9'0
April-—, .. .. .. .. 16'2 August, .. .. .. .. 177 December, .. .. .. 7'7
General mean daily range, l4'08 Now if m be taken inversely as the mean range of temperature, 1', or m = a
Mlosvthe accordance between the calculated and observed values of the co-ef
ficient is very close:
(a = 2'29.) value of m. value of m.
for the 7 coldest months, by calculation, 2'98 by observation, 2'88 7 warmest months,—--— 1'86 —_—— 1'97 5 coldest months, ————————-—— 3'36 3'06 5 warmest months, —-—- 1'73 -— 1'73
and so on throughout. The concluding remarks of Mr. Pn11.LrP’s explain the hypothesis he has framed for the explanation of the phenomenon which led to the experiments, and to us it appears most clear and conclusive.
“ So remarkable and continued an accordance between the co-eflicients fixed by observation and those derived by two methods from a very simple view of the condition of the air as to heat and moisture, appears to me decisive of the question as to the general cause of the variation of the quantity of diminution of rain at any one height above the ground. It has already been shown how strictly the observations warrant the conclusion that the ratio of diminution of diferent heighfs is constant through the whole year. It is therefore rather as a matter of very probable inference than a plausible speculation that I offer the hypothesis, that the whole difference in the quantity of rain, at different heights above the surface of the neighbouring ground, is caused by the continual augmentation of each drop of rain from the commencement to the end of its descent, as it traverses successively the humid strata of air at a temperature so much lower than that of the surrounding medium as to cause the deposition of moisture upon its surface. This hypothesis takes account of the length of descent, because in passing through more air more moisture would be gathered; it agrees with the fact that the augmentation for given lengths of descent is greatest in the most humid seasons of the year; it accounts to us for the greater absolute sizeof rain-drops in_
the hottest months and near the ground, as compared with those in the winter and on mountains; finally, it is almost an inevitable consequence from what is known of the gradation of temperature in the atmosphere, that some effect of this kind must necessarily take place. The very common observation of the cooling of the air at the instant of the fall of rain, the fact of small hail or snow whitening the mountains, while the very same precipitations fall as cold rain in the valleys where the dew point may be many degrees above freezing is enough to prove this. A converse proof of the dependence of the quantity of rain at different heights on the state of the air at those heights, is found in the rarer occurrence of a shower“'falling from a cloud, but dissolving into the air without reaching the ground. Lastly, I cannot forbear remarking, that this hypothesis of augmentation of size of the elementary drops agrees with the result that the increase of quantity of rain for equal lengths of descent is greatest near the ground: for whether the augmentation of each drop be in proportion to its surface or its bulk, the consequence must be an increasing rate of augmentation of its quantity as it approaches the ground.
“ The direct mathematical solution of this problem, now that the laws of cooling and of the distribution of temperature have undergone such repeated scrutiny, may perhaps be attempted with success; but for the purpose of eliminating the effects of periodical or local modifying causes, it is desirable that observations on the same plan should be instituted at many and distant p1aces,—both along the coasts and in the interior,—iu the humid atmosphere of Cornwall and in the drier air of the mid-land counties. Always, at least three stations should be chosen, as open as possible, one of them very near to the ground : their relative heights, the mean temperatures, the mean ranges of temperature, and the mean dew point for each month should be ascertained. It would be useful to measure the size of the rain-drops, and, if possible, their own temperature. The height of clouds according to the plan of Mr. DALTON, in his Meteorological Essays, and the direction and force of wind should be noted, and distinctions made between suow, hail, and rain, Some of these data I have not yet found the means of procuring, partly in consequnce of the great labour and time required, and partly from the difliculty of well arranging the experiments themselves. But since it is now ascertained that the general results follow some settled laws, and that the effects may be very well appreciated at moderate heights, I hope not only to procure these, but also several other data towards the completion of the theory of this curious subject, the patient investigation of which cannot fail to give us new and penetrating views into the constitution of the atmosphere.”
It will be a curious subject of investigation to determine, the applicability of the law of altitude and moisture to this country, and to fix the value of m. This latter may, in some measure,be done from the long series of observations published in the Surveyor General’s Meteorological Register : but for the law of height, we shall require a higher station, and we invite any zealous meteorologist who may have leisure to fix his pluviameter on the top of the OCHTERLONY monument ; a chuprassee may easily be taught to observe it daily throughout the rains.
2. An unusual Sea-Monster in the Bay.
On my voyage to Madras (in May last), I saw a most extraordinary fish, and which had never before been seen by any seaman on board, although some of the oflicers and crew had been employed in the whale fishery. It was of the size of a whale, but differing from that animal in shape; spotted like a leopard, in a very beautiful manner : it came close under the stern of the ship, during a calm, and we had a magnificent opportunity for yiewing it : it had a very large dorsal fin, which it moved about with great rapidity when made angry in consequence of the large stones that we threw down upon it rashly ; for it possessed suflicient strength to have broken the rudder and stove in the stern of the ship. Several large fish (seemingly Dog-fish), about a cubit in length and upwards, were gamboling about the monster, entering its mouth at pleasure and returning to the water again. The following will give you some idea of its shape. The mouth very large, dorsal fin black or dark. brown, tail also; body covered with brown spots like a leopard, head lizard. shaped. May it not be the Plesiosaurus, or a species of that fish known to have existed formerly in the waters of the ocean? Having given you this statement, it is proper that I should give you ,the names of those who were also eye-witneggeg of the existence of this extraordinary animal, They are as follows:
1. Captain Tmaaru, at that time commanding the ship “ Cashmere MW. chant,” now commanding the “ Competitor.”
2. Mr. Sninnnm, Mr. Pixn, and Mr. Larmnns, oflicers of the vessel.
The above gentlemen will corroborate my statement : Captain TINGATE and Mr. SMELLIE were old sailors, and had never before seen the fish, or one resembling it. There were also several European seamen on board, not one of whom had ever seen it before.
[All we can venture to say on this authenticated account is, that the monster described is nota Plesiosaurus as Lieutenant Fonnr suggests; as that reptile has no “ dorsal fin.” What it may be, we must leave others more competent to decide, but the unusual nature of the notice should by no means prevent the insertion of a description supported by such unequivocal evidence.--En.]
3. Suspension of the Survey of the B1-ahmaputra River.
For the last four years, an accurate trigonometrical survey of the Brahmaputra has been in progress, to connect the map of this river from Goalpéra, where it terminated in Captain WILcox’s Survey of the Assam Valley, (see the 138th sheet of the “ Indian Atlas," or the lithographed map in the 17th volume of R.esearches,) with the surveys of the Ganges, the Sunderbans, and finally with the grand meridional arc. Captain WILCOX and Lieutenant OMMANNEY, Engineers, completed the measurement of the J enai, which now forms the main stream of the Brahmaputra, from Jumalpur to its confluence with the Ganges at Jafirganj, and the latter oflicer had in 1830 since been engaged in tracing the line of the river from goalpara round the difficult country at the root of the Kasia mountains, to within 30 miles of Dacca, when a sudden order of Government lately directs the whole work to be suspended, and in fact, allthat has been done, to be rendered comparatively useless for want of the connecting link which it would not have taken three months to complete I Geographers at home will he at a loss, as we ourselves are, to account for a measure apparently so impolitic, and we cannot help thinking, that a word of explanation to the proper authorities would still be in time to remedy the mistake.