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too much exficcation; the latter fith kinds, which is of a middle na. .'. being, from their general structure . ture between the phocæ, and the and conftitution, made it to bear, real fishes of the sea, in one pecu. and live in, the water; the for. liar respect. This is the class of mer, by their conftitution and the phocenæ, or porpusles, of forms, to breathe, and dwell, in which there are several species ; the air.

.. . and these have lungs, and there. But it may be asked, why eels fore are forced to come up to the and water snakes are capable of surface to breathe at very short inliving longer in the air than the tervals ; but, when brought on other kinds of fish? this is an. Tore, have no progressive loco, Swered, by considering the provi- mocion. So that, having lungs, dential care of the great creator they resemble the phocæ, and, in for thefe and every one of his every other respect, the real fishes : creatures : for, since they were of the sea. capable of loco-motion by their Blafius, in his Anatome Ani. form, which they 'need not be if malium, page 288, gives an acthey were never to go on thore, it count of one of these taken and seemed necessary that they should brought on shore alive; che peobe rendered capable of living a ple let him lie, to see how long he considerable time on fhore, other could live out of the water; and wife their loco.motion would be in he continued alive only about fevain.. How is this provided for ? ven or eight hours, and exhibited why in a most convenient manner ;' a kind of hisfing voice. : for this order of fithes have their From what has been said, it. branchiæ well covered from the will, I hope, appear rational, that external drying air, and are also these are the only two orders that furnished with a limy mucus, can properly be deduced from the which hinders their becoming crisp class of amphibious animals; and and dry for many hours, and their that the genuses of either order are very kins always emit a, mucus very few in the animal world. liquor, which keeps them fuppleni : . and moist for a long time; where. as the branchiæ of other kinds of A letter from James Parfons, M. D. fish are much exposed to the air, F. R. S. to the right honourable and want the fimy matter to keep "the Earl of Morton, president of them moitt. Now, if, when any t he Royal Society ; on the double of these is brought out of the horns of the Rhinoceros. water, it was laid in a vessel without water, he might be kept : My Lord,. . alive a confiderable time, by only kecping the gills and surface of W HEN I had the honour of the skin constantly wet, even with V laying my natural hiftory out any water to swim in... of the rhinoceros before this learn. * Before I dismiss the first part of ed society in 1743, which is printmy discourse, I must beg your pa ed in number 470, page 523, of tience, while I mention something the Transactions, I had not an that relatos to a family among the opportunity of Newing a double

horn

horn to the members; I have this difference, that these changed therefore taken this first occafion the euros for ursos, as imagining to entertain the present members they were rather bears than bulls with a fight of a noble specimen that were thrown up by this noble

of the horns of an African rhi. animal. · noceros, brought from the Cape Our then worthy president Mar. of Good Hope, by my curious tin Folkes, esquire, had seen my and worthy friend William Ma. account of this subject, at the end guire, esquire, among many other of which I endeavoured, however curiofities; presuming that few of presumptuously, to defend Marthe society have ever feen a pair of tial's reading against Bochart and the like kind. But what renders the other eminent persons mentionthis subject the more particular, ed; and defired I would let it be and worthy of observation, is, that read and printed, which I very by means of knowing there is a readily agreed to, as his requeit fpecies of this animal, having al. did me much honour. ways a double horn upon the nose, Before my paper was printed in Africa, Martial's reading is Mr. Maittaire and Doctor Dougsupported againft the criticism of las died; and the learned Doctor Buchart, who changed the true Mead was the surviving critic, uptext of that poet, in an epigram on this line, of the three. Upon upon the strength of this animal ; this occasion, therefore, I have a for when Domitian ordered an ex. double pleasure; first, in amusing hibition of wild beasts, as it was the present gentlemen with a moft the custom of several emperors, curious fpecimen in nitusal hifthe poet says : The rhinocerostory; and, secondly, in rememtoss'd up a heavy bear with his bering in this place, the nice can. double horn:

dor and generosity of Dr. Mead Namque gravem gemino cornu fit

upon that subject. For, about four

1 months after the paper was printed, extulit ursum.

he received a present of several cu. and as Bochart knew nothing of a rious shells, seeds, &c. and with double horn, he changed this line them the bones of the face of a both in reading and sense thus : young rhinoceros, with two horns,

in fitu, all entire, by a captain of Namque gravi geminum cornu fac an African trader, who brought extulit eurum.

them from Angola. i as if two wild bulls were toffed up As soon as he saw the horns, into the air, by the strong horn of he sent to invite me to breakfast, the rhinoceros.

and there, in company, ingenu. · Mr. Maittaire adopted the no. ously gave up his paft opinion, tion of a single horn, but was of and declared for Martial; and, opinion that the geminum eurum of indeed, I must add to the praise of Bochart ought to have been plu. that great man, that, as I was ral, geminos euros, as being more happy in being frequently at his elegant ; and he was followed by house, I was witness to many such Doctors Mead and Douglas, with instances of the moft disinterefted

candout

candoúr and generosity, where any which you was pleased to take of part of science was the topic, a my letter upon the late comet, did mong his select friends

not make me more careful to ob- This anecdote I thought proper serve whatever I thought might to mention upon the present occa. tend to improve the knowledge of fion; nor can too much be said to nature, which is a capital part of his honour, among all lovers of the laudable design or the society. philosophical learning. I am

Your lordship knows, that my Your lord ship's

situation exposes me to every blait most obedient servant; that blows, and affords à fair op

, James Parsons. portunity for measuring the veloP. S. The dimensions are as city of the wind (the force of which follows: viz. The length of the I am, so often, obliged to feel). I anterior horn, measuring with a have attempted to determine this ftring along the convex fore part, by letting light downy feathers fly is 20 inches; perpendicular height in the wind (the method, I under18 ; circumference 211 at the stand, used by the ingenious Dr. base; the posterior horn is in perá Derham); but cannot say, in all pendicular' height 191; circum: the trials I have made (though I . ference round the base 18; length have let fifty of these feachers Hy;, of both bases together upon the one after the other, at a time) nasal bones 141 and the weight of that I have ever seen above one, both together is 14 pounds 10 or two at most, upon which I ounces.

could have founded a calculation. The rhinoceros of the year 1739, The velocity of the wind near described in the transactions, was the earth is very unequal, upon three years old, and the horn not account of the frequent interrupthree inches high; and hence by tions it meets with from hills, trees, comparing that with this, one may and houses; and even in open imagine this to be many years old, plains; the surface of the earth, perhaps above twenty ; and that though much smoother than it comthis animal lives to a great age. monly is, must reflect and inter• It is also plain that the horns rapt such a fluid as the air, and are perpetual, as are those of oxen, occafion great irregularity in the

velocity of its current: this is the

reason, when a feather is let fly', A letter to the president of the royal with the wind, why it seldom, if .

Society; containing a new manner ever, describes a strait line, but of measuring the velocity of wird, moves sometimes in a kind of spiral, and an experiment to ascertain to now high, and then low, some. what quantity of water a fall of times to the right, and then again Inow is equal.

tớ the left; and why two feathers

let fly at once, feldom, if ever, Kirknewton, May 13, 1766. keep together, or describe similar My lord,

lines, T SHOULD think my self moft But, at some considerable dir.

unworthy of the honour which tance from the earth, the velocity your lordship and the royal focic of the wind seems to be regular cty have done me, if the notice and steady: nothing can be more VOL. X.

uni.

G

uniform than the velocity of a that was diftinét, and well defined, cloud in the sky appears to be, just touched a south and north line, even in the greatest storm : it is which I had marked upon the like a ship carried away insensibly ground ; at that inftant I be. by a smooth and gentle currení, gan my reckoning, and followed passing over equal spaces in equal the shadow with my eye in its protimes. This suggested the thought, gress, counting seconds all the that the motion of a cloud, or its while by the clock, until I had Shadow over the surface of the reckoned up 15 seconds; then I earth, would be a much more observed exactly where the afore. proper measure of the velocity of said edge of the shadow was. the wind.

This experiment I repeated ten In the end of March 1763, I times in half an hour, and seldom had as favourable an opportunity found the difference of a second, of putting this method into prac- in the time which different clouds tice, as I could have wished for: took to move over the fame space. the storm was exceeding high, and On the 5th of May current, I moved with vaft velocity; the sun repeated the trial four different was bright, the sky clear, except times, the sun being also near where it was spoited with light the meridian, the wind in the floating clouds; I took my station weft, with light clouds floating in in the north window of my dining a clear sky as formerly; and found room, near the clock, from which that the shadows of different I had a free prospect of the fields ; . clouds took some of them 44, and the sun was in the meridian, the others 45 seconds, to pass over the wind due west intersecting his rays same space which they had moved at right angles; I waited until the over in 15 seconds, in the former fore-part of the shadow of a cloud, trials.

Feet This space measures exactly 1384=fpace paffed over in 15 seconds, which multiplied by 4

gives 5536=fpace passed over in one minute, which multiplied by 60

gives 332,160=space passed over in one hour. Which space is =62.9 English that the shadow took 95 seconds miles per hour, the velocity of the to pass over the above space, which wind in March 1763.

gives the velocity of the wind at One third of this (or 21 miles the rate of 9.9 English miles per nearly) shews the velocity of the hour. wind on May the 6th, when it ; Thus, by having several lines blew a fresh gale.

in different directions of a known 'This day, May 12, there was a length marked upon the ground, small wefterly breeze, the velocity one may easily (and with great acof which I measured upon the curacy, I imagine,) measure the same line, the sun being 10 mi velocity of the wind. If a person nutes past the meridian, and found was provided with an instrument

for

for measuring the force of the means I took op all the snow from wind, it would perhaps be worth top to bottom in the jug ; this while to observe whether, when snow I melted by the side of a fire, the velocities of different winds and the 6.2 inches of snow yielded were the same, (or nearly fo) the fix tenths of an inch deep of water forces of these winds did not vary in the same jug. After emptying with the seasons of the year, the the jug, I dried, and weighed it in points of the compass from which a balance, and took up the same the wind blows, and also with the quantity of snow in it' as before, different state of the barometer and weighed it again, and found the thermometer, since the momentum weight of the snow taken up, and of the wind depends not only from this weight computed what upon its velocity, but also upon quantity of waier it should have its density.

produced, and found that it ought From the end of March 1765, to have produced fix tenths of an to the end of March last, we, in inch and one twentieth of an inch this part of Scotland, had very lit. more : then I diffolved the snow, tle rain, and less snow in propor- and found that it yielded a quan. tion; our rivers were as low, tity of water in the bottom of the through the winter, as they use to jug, fix tenths of an inch deep, be in the middle of summer; springs as in the former experiment. failed in most places, and brewers The difference of one tw ntieth and maltsters were obliged, even in of an inch in the depth of the wa. winter, to carry their water at a ter, betwixt the weight and the confiderable distance; I was much melting of the snow, was proba. afraid there would not be moisture bly owing to an exhalation from enough in the earth for the pur. the jug, while the snow was melt. poses of vegetation, if this season ing by the fire, for I observed a should set in as dry as the former, steam sometimes rising from it. A before we got a new supply of rain. great or lesser degree of cold, or In the end of March last, we had of wind, while the snow falls, a fall of snow; and, as I did not and its lying a longer or shorter remember to have ever read an ac. while upon the ground, will oc. count of such an experiment, I cafion a difference in the weight wished to be able to determine, to and in the quantity of water pro. what quantity of rain this fall of duced from a certain number of snow was equal.

cubic feet, or inches, of snow ; The snow had been falling from but, if I may trust to the above five o'clock the former evening, trials, (which I endeavoured to till ten o'clock the next day; about perform with care) snow, newly cleven o'clock I meafured the depth fallen, with a moderate gale of of the snow, and found it to be 6.2 wind, freezing cold, which was inches ; then I took a stone jug, the case of the snow I made the holding about three English pints, trials upon, the 27th of March laft, and turned the mouth of it down. will produce a quantity of water wards upon the snow measured, equal to one tenth part of its and where the ground below was bulk; or the earth, when covered smooth and hard ; and by this with snow, ten inches deep, will

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