VOL. XLIII.] PHILOSOPHICAL TRANSACTIONS. 101 



The interment of this man and stag seem to me to have been accidental, by 

 their falling into a chasm, or wide cleft of the rock, in very early times ; which 

 has since closed up, and grown over them, by the accretion of the marly sub- 

 stance, which environs the skeleton, &c. ; and in time perhaps will grow as hard 

 as the tuft, and the rest of the rock. 



Concerning a large Slone found in the Stomach of a Horse. By Mr. Wm. fVat- 



son, F.R.S. N''475, p. 268. 



Mr. W. here offers some observations on the calculus, sent him for exami- 

 nation by Mr. Woolaston, who informed him that it was found in the stomach 

 of a coach-horse ; and that it then weighed 3 pounds 2\ oz. Avoirdupois. It 

 seems the poor creature was observed frequently to be in violent pain; and 

 would sometimes eagerly turn his head to one of his sides, and sometimes to the 

 other, as though he endeavoured to bite out that which annoyed him ; and that 

 he died, after having taken various remedies, which the farriers administered. 

 When Mr. W. weighed this stone about half a year after the former its 

 weight was 2 lb. and 4 oz. ; so that in about half a year, it had lost lib. loz. 

 \. Its figure was spheroidal, as these sort of stones generally are ; its periphery 

 174- inches, by l6i inches ; which are very near the same dimensions this stone 

 had when first found. Its surface irregular, somewhat resembling the inequali- 

 ties on the surface of the brain : all the projecting parts of which are polished, 

 from their friction against the sides of the stomach. It was of a dark-brown bilious 

 colour, and very like to a species of pyrites, and was by much the most specifically 

 heavy of this sort he had ever seen. 



Having, from sawing the stone, a quantity of its powder, he was induced to an 

 inquiry into its constituent parts by way of analysis. He first let fall 2 small 

 pieces of this stone into water almost boiling : they immediately sunk, but rose 

 again, and continued alternately rising and sinking a considerable time. This 

 was occasioned by the quantity of air bubbles, which the heat rarefied ; but the 

 air was detained by the mucus, which seemed to connect the particles of the 

 stone together ; and which, though diluted by the hot water, was tenacious 

 enough to form bubbles of size sufficient to buoy up the pieces of stone ; the 

 rarefaction becoming greater, the bubbles burst, and the stone fell to the bottom : 

 but rose again, in like manner, at the expulsion of more air. Dr. Hales like- 

 wise found great quantities of air in the human calculus. 



Mr. W. infused 2 drams of this powder in 2 oz. of boiling water: this infusion 

 he filtered when cold. It was of a light brown colour, and of a bitterish saline 

 taste. He calcined what remained of the powder after the infusion, till the 

 whole was black, and then it weighed a dram and 3 grains. He made the fol- 

 lowing trials with the infusion : 



