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went further in order to examine the quicksilver when it was made solid. He poured quicksilver into a glass tube as thick as one's finger, closed at bottom, but open at top. The quicksilver in this cylinder, which was about one inch and half long, froze in three quarters of a minute; and he observed that it became solid, perfectly resembling other metals, except iron: it continually contracted, and its surface, which was at first pretty high, soon sunk very low. This cylinder of frozen quicksilver sunk to the bottom of fluid quicksilver, in the same manner as is observed of other metals except iron. We know the contrary happens with regard to water frozen and other fluids, which extend as they become solid, and their ice swims in the fluid matter of which they were produced.
Dec. 26 in the morning, between 9 and 10, the cold became extremely sharp at 211o, and such as exceeded the greatest degree of artificial cold fixed by Fahrenheit; for 40° below zero, in Fahrenheit's thermometer, is equal to 210° of that of De Lisle.
Mr. Braun repeated this experiment again exactly with the same success with that of the day before. The counsellor and professor Lomonossow made the same experiment on the same day; and by means of aquafortis the cold came to 495 degrees. He then poured in spirit of common or sea salt, and the quicksilver fell down in the thermometer to 554 degrees; and in taking the thermometer from the mixture the quicksilver continued to fall in the open air to the 552d degree. He threw yet into the glass a little more snow, pouring on it some oil of vitriol, and suddenly the quicksilver fell to 1260 degrees. He then broke the ball, and found the mercury changed to a solid body. The quicksilver, which yet remained in the tube, was also become solid, and appeared like a loose silver wire attached to the ball, which was flexible every way. He gave the ball of quicksilver several blows with a turned ax, and it became flat like a half ruble, or English half crown; but receiving thereby some cracks, it dissolved in about 20 minutes. These experiments were made when the air was at about 208 degrees of cold.
It must be remarked that distilled quicksilver only was made use of in every experiment; nay in some the quicksilver was revivified from sublimation. There can therefore be no suspicion that what they used was impure or mixed with any heterogeneous matter. This appears to have happened to Mr. De Lisle de la Croyere, when he says, that in Siberia he found the quicksilver congealed in the barometer: and even his papers, which are in the academy, show that he made a mistake in his remarks; for according to them the mercury became solid as soon as it fell to about 195° or 200°: but the mercury which is pure does not congeal at that degree; for otherwise it would not be very extraordinary with us to see it take a solid form, because it is not rare to find the cold at this degree 3 Q
here. We may believe that the quicksilver used by Mr. de la Croyere was impure, and therefore might sooner become an amalgama than mercury. Though in the experiment made by Mr. Lomonossow the quicksilver fell to 1260°, yet this philosopher says, that he could not sufficiently observe in his hurry whether the ball might not have received some crack, and the quicksilver thereby perhaps might have had liberty to fall the lower, which otherwise would not have happened; for the same thing happened to Mess. Braun, Zeicher, and Æpinus, that the balls of their thermometers were cracked and broken.
In making these experiments, it is to be observed, that it is necessary to use fuming spirit of nitre, or of such as is evaporated till the fumes become red; for the common aquafortis which is used had not the desired effect. Mr. Æpinus has found that this experiment is very easily and speedily made in the following manner. Take spirit of nitre, cooled as much as possible, and with it half fill a wine-glass, throwing in as much snow at the same time, and stirring it till it becomes of the consistence of pap: then you have almost in an instant the necessary degree for the congelation of the quicksilver. Now in reflecting on the procedure of other philosophers, especially of Mess. Muschenbroek and Reaumur, for producing artificial cold by the commixtion of snow with aquafortis, as the former has mentioned in his edition of the Experiments of the Academy of Florence, tom. i. p. 174, and Mr. Reaumur, in the Memoirs of the Academy of Sciences of Paris for the year 1734, it is astonishing how it happens that these learned men have not obtained, by a great deal, the degree of cold produced by the gentlemen of the academy of Petersburgh; for their manner of making the experiments does not seem to differ much from that of Mr. Braun, as to what relates to any essential circumstances, nor from the manner mentioned before, so as to hinder them from producing effects nearly equal. Indeed a certain degree of external cold appears absolutely necessary to the experiment. Mr. Epinus, who made it the 28th of December, in a room where De Lisle's thermometer showed 122 degrees of cold, cooled the spirit of nitre in liquifying snow to 150 degrees, and the snow which they used came to the same degree; in making the mixture, the result was an augmentation of cold to 300 degrees. It must then happen, that they had obtained the surprizing degree necessary to congeal the mercury; which Mr. Zeicher also at length obtained; the degree of cold of the air being the 175th degree of De Lisle's thermometer, or the 30th of that of Fahrenheit.
LXV. Of a Complete Luxation of the Thigh Bone, in an Adult Person, by External Violence. By Mr. Charles White, Surgeon at Manchester. p. 676. As Robert Hogg, (a farmer in Clyfton, about 4 miles from Manchester) a strong, robust, middle-aged man, was taking a load of wheat from off a horse
on the 20th of March 1759, his foot slipping, he fell backwards; his breech on the pavement, and the load of wheat on his belly and thighs. The servants carried him into the house, and laid him on a bed, where he remained in the most racking torture, when Mr. W. came to him, which was about 2 hours after the accident happened. He found his right buttock as large again as the other; the knee and foot of the same side turned inwards; and the thigh much shortened. On endeavouring to make the thigh perform its rotatory motion, there was not the least crackling to be heard. This convinced him that the head of the bone was thrown out of the acetabulum; and on examination he could distinctly feel it under the glutei muscles: to which situation of it, and not to any bruise, he was now satisfied that the size of the buttock was owing.
He soon reduced it by the following easy and very simple method: some napkins being first wrapped round one of the posts at the foot of the bed, to prevent its galling him, he ordered the patient to be laid on his back, with one leg on each side the post, and then directed 3 or 4 assistants to pull at the dislocated limb, the post now placed to his groin being a fixed point to pull against. While they were making this extension, Mr. W. clapped his left hand on the head of the bone, to help it into its place; and at the same instant, with his right hand, turning the knee outwards, threw the bone into the socket with the greatest facility imaginable, but with such an uncommonly loud noise as greatly astonished all who were present.
He was perfectly easy from that moment; the enlargement of the buttock entirely subsided. In a fortnight he was able to move about without assistance; and in 2 months afterwards walked as far as Manchester, being then quite sound; and the limb that had been dislocated of the same length with the other.
Remarks. Both ancients and moderns have fallen into great errors in regard to the treatment of accidents that have happened to the hip joint. The ancients, who for want of frequent opportunities of dissecting bodies, were ignorant that the neck of the femur was often broken, always imagined it to be luxated. Their patients were therefore sometimes tormented (in hopes of a reduction) without any advantage; and this want of success made the surgeons at other times abandon their patients when they might have been relieved. The moderns have fallen into a contrary extreme, but attended with as bad consequences. Boerhaave in particular was of opinion that there never was a dislocation of the thigh bone by any external violence, but that the head of it was commonly broken off at its neck near the great trochanter. The opinion of so learned a man has had such weight with the generality of the profession, that it has been taken for granted that in these cases the neck of the bone was always broken; consequently the reduction was seldom attempted, and the unfortunate patients remained
cripples during the rest of their lives. But the point is now, Mr. W. thinks, cleared up beyond the possibility of a doubt.
In the 2d vol. of the Memoirs of the Royal Academy of Surgery at Paris, there are 2 cases related to show the resources of nature, where luxations of the thigh-bone have not been reduced. Here it appears (from examination after death), that in the first case the bone was thrown out upwards and outwards, the cotyloid cavity greatly diminished in size, and its figure changed from round to oval. The head of the femur was received into another cavity formed on the os ileum, under the gluteus minimus, which served it as a capsula to secure it within this preternatural cavity. This accident was occasioned by a fall when the patient was a child. She was afterwards able to walk about, though she continued a cripple to the time of her death, which happened at the age of 68. In the other case the bone was luxated downwards and inwards, and the head fixed on the foramen ovale.
There is a case too related in the Edinburgh Essays, vol. 2d, of a man at Worcester, who had the head of the bone thrown out of the acetabulum, and lodged in the groin. It was with some difficulty reduced, and the man suffered no other inconvenience than that of the leg's being about a quarter of an inch longer than the other.
To these Mr. W. adds, that about 30 years ago his father was sent for to a man who had luxated his thigh bone 3 or 4 days before. The head of it lay in the groin, which the surgeon who was first employed did not discover. However, it was immediately replaced, and the patient recovered the use of his limb in a very short time.
From what he had said, he would by no means have it concluded that the neck of the bone is not sometimes broken, or that it is not even oftener broken than luxated: but from the case which had fallen directly under his notice, joined to those which he had above recited, he thinks it must appear very clear, that it has been frequently luxated, and that in 2 different ways.
LXVI. Conjectures on an Inedited Parthian Coin. By the Rev. John Swinton, B.D., of Christ-church, Oxon. F.R. S. p. 680.
This is a small brass coin, nearly of the size of the middle brass ones, but in bad preservation.
LXVII. Of a Stony Concretion taken from the Colon of a Horse. By Mr. H. Baker, F.R.S. p. 694.
Mr. B. laid before the R. S. of a stony concretion, formed in the colon of a horse, which was sent to him from Norwich by Mr. W. Arderon, F. R.S.
This horse was 25 years old, had been often ill, and under the farrier's care; which made Mr. A. desire to have it opened when dead.
The whole stone, when first taken out, weighed 10 lb.: and Mr. A. caused it to be sawed in two, that a better judgment might be made of the manner of its formation. Several smaller concretions were also found in the colon; but
they were much less solid, and more irregular than the large one. This ball was full 7 inches in diameter, and consisted of many laminæ or coats, which formed a number of concentric circles, around a nucleus in the centre, which seemed to be a small shiver of black flint. Fifteen or 16 of these coats were easily distinguishable, and some had been broken off: they varied something in colour, and were in general so stony that they would probably take a pretty good polish. The coats differed in thickness, according perhaps to the time they were in forming: for it should seem, if conjecture might be allowed, that each coat was formed in a longer or shorter time, according to its thickness; and that between the finishing of one coat, and the beginning of the next, there was some interval of time, and some suspension of that attractive power whereby, or of that component matter whereof, the several coats were respectively formed.
LXVIII. An Explanation of the Modes or Tones in the Ancient Grecian Music.
LXIX. An Inquiry into the Measure of the Roman Foot. By Matthew Raper, Esq., F. R. S. p. 774.
The ancient foot-rules now remaining; the representations of the foot in sculpture; and the measure of it, derived from the congius, differ so much among themselves, and from each other, as to be insufficient evidences separately: and the great disagreement of the foot from the congius, with the rest, has not hitherto been satisfactorily accounted for. The foot-rules found in old ruins at Rome are of various lengths; and the age of none of them being certainly known, no precise measure can be determined from them, otherwise than by taking a mean from such as appear to be most perfect. But though this may have been the foot in use at some time or other, yet as these rules are probably of different ages, both the greatest and least of them may have answered to the standards of their times. For though we have no account of any alteration ever made in the standard of the Roman foot, yet the wear of a standard measure by use, and the making new to replace the old ones, must probably create a difference; especially as the Romans had not those inducements to so precise an accuracy in these matters as the later discoveries in natural philosophy (particu