157 



ers ; the animal matter which they contain is chiefly gelatine and a 

 little resin ; and the fibrous vegetable matter appears to have been 

 derived from the inner coat enveloping the farinaceous part of the 

 oat. From other cases, which the author mentions at the conclu- 

 sion of his paper, it appears that oatmeal has not unfrequently con- 

 tributed to the deposition upon intestinal concretions ; and from the 

 analyses which he quotes, the same fibrous matter has been detected 

 in them hy other chemists. 



On the Concentric Adjustment of a Triple Object-Glass. By William 

 Hyde Wollaston, M.D. V.P.R.S. Read December 13, 1821. 

 [Phil. Trans. 1822, p. 32.] 



The centering of a triple achromatic object-glass has always pre- 

 sented considerable difficulties to practical opticians, which Dr. Wol- 

 laston has succeeded in removing, with regard to an excellent teles- 

 cope in his own possession, by observing the relative position of the 

 fifteen small images of aluminous object near the eye-glass, which are 

 formed by the binary combinations of the reflexions of the six sur- 

 faces concerned, and which are seen by an eye situated beyond the 

 object-glass, and assisted, if required, by a lens. When these images 

 are all in the same right line, it is obvious that the glasses are not 

 only well adjusted together, but that each is well centered ; and by 

 means of four screws acting on each glass, Dr. Wollaston was able 

 to make the adjustment so complete, as considerably to improve the 

 powers of the instrument. 



On a New Species of Rhinoceros found in the interior of Africa, the 

 Skull of which bears a close Resemblance to that found in a Fossil 

 State in Siberia and other Countries. By Sir Everard Home, Bart. 

 V.P.R.S. Read December 13, 1821. [Phil. Trans. 1822,^. 38.] 



The animal described in this paper was shot about 300 miles west 

 of La Goa Bay, 6 miles from the city of Mashow, and 1000 miles in 

 a straight direction from the Cape of Good Hope. It is graminivorous, 

 and not gregarious. The skull is 36 inches long ; and the position 

 of the horns, though differing in many respects from those of other 

 existing species, bear so close a resemblance to those of the fossil 

 skulls from Siberia, as to leave no prominent characteristic mark be- 

 tween them ; hence the author doubts whether many races of ani- 

 mals supposed to be extinct are really so : he thinks it probable that 

 they may have retired to uninhabited parts of the globe. The small 

 capacity of the skull of the rhinoceros, as compared with that of the 

 elephant, accounts for its inferior intellect, for the extreme difficulty 

 of rendering the animal tractable, and for the failure of all attempts 

 that have been made at taming him ; and renders it not improbable 

 that the unicorn, not to be tamed, mentioned by Job, is identical with 

 the rhinoceros, since no other animal so devoid of intellect has ever 

 been described. In that age, says the author, the short horn, which 



