270 PHILOSOPHICAL TRANSACTIONS. [ANNO 17Q8. 



which were found to consist of phosphate of ammonia, phosphate of lime, and 

 animal matter, without containing uric oxide. The difference in the constitution 

 of urinary concretions may depend on the difference of the urinary organs of dif- 

 ferent animals, on the food and drink*, and on the various diseased and healthy 

 states of the urinary organs. 



I have not found the uric oxide in the urinary concretions of any phytivorous 

 animal; but whether it would be formed in the human animal when nourished 

 merely by vegetable matter, must be determined by future observations. In the 

 mean time, it is warrantable to conclude from analogy that it would not, and the 

 application of this fact to practice is obvious; but I now purposely avoid making 

 any practical inferences, till I can, at the same time, state a number of facts I have 

 collected, relative both to concretions and to the urine itself. 



///. On the Discovery of Four Additional Satellites of the Georgium Sidus. The 

 Retrograde Motion of its old Satellites Announced; and the Cause of their Dis- 

 appearance at Certain Distances from the Planet Explained. By fVm. Herschel, 

 LL.D., F.R.S. p. 47. 



Having lately been much engaged in improving my tables for calculating the 

 places of the Georgian satellites, I found it necessary to re-compute all my obser- 

 vations of them. In looking over the whole series, from the year of the first dis- 

 covery of the satellites in 1787 to the present time, I found these observations so 

 extensive, especially with regard to a miscellaneous branch of them, that I re- 

 solved to make this latter part the subject of a strict examination. The observa- 

 tions alluded to relate to the discovery of 4 additional satellites: to surmises of a 

 large and a small ring, at rectangles to each other: to the light and size of the 

 satellites; and to their disappearance at certain distances from the planet. In this 

 undertaking, I was much assisted by a set of short and easy theorems I had laid 

 down for calculating all the particulars respecting the motions of satellites; such as, 

 finding the longitude of the satellite from the angle of position, or the position 

 from the longitude: the inclination of the orbit from the angle of position and 

 longitude: the apogee: the greatest elongation; and other particulars. Having 

 also calculated tables for reduction ; for the position of the point of greatest elonga- 

 tion; and for the distance of the apogee, or opening of the ellipsis; and also con- 

 trived an expeditious application of the globe for checking computations of this 

 sort, I found many former intricacies vanish. By the help of these tables and 

 theorems, I could examine the miscellaneous observations relating to additional 

 satellites, on a supposition that their orbits were in the same plane with the 2 al- 

 ready known, and that the direction of their motion was also the same with that 

 of the latter. 



* I found the stomach-concretion called Oriental Bezoar, to consist merely of vegetable matter ; as 

 did the intestinal concretion of a sheep.— Orig. 



