Sequel to a Paper on the tendency to Calculous Diseases, and on the 

 Concretions to which such Diseases give rise. By John Yelloly, M.D. 

 F.R.S. SfC. Read June 17, 1830. [Phil. Trans. 1830, p. 415.] 



The author, in a paper published in the last volume of the Philo- 

 sophical Transactions, gave the analysis of 328 calculi contained 

 in the collection of the Norfolk and Norwich Hospital; and has 

 been since enabled to complete the analysis of the 335 remaining 

 specimens, which have now been divided. The results of the ana- 

 lysis are given in a tabular form, exhibiting in the order of their 

 occurrence from the centre, the consecutive deposits of the different 

 materials of which the calculi are composed, according to the most 

 prominent character of such material. The most remarkable cir- 

 cumstance brought to light in the course of this investigation, is 

 the discovery of the presence of silex in one specimen composed 

 principally of oxalate of lime, and weighing about 5 grains. The 

 particles of silex were very minute, and were imbedded in, and dif- 

 fused through, the oxalate of lime. Three examples of a similar 

 occurrence are quoted by the author. 



The paper concludes with a few remarks on the statistical con- 

 clusions stated in his former communication. He thinks there is 

 reason to believe that the average number of calculous disorders in 

 Scotland has been much underrated ; on the other hand, the prone- 

 ness to those complaints is very small in Ireland. A much larger 

 proportion of calculous cases occurs in towns than in the country. 



