







410 



Lithiasis. 



and the formation of the muscles and glands. The general 

 tendency of the animal system is organically indicated by the 

 organs of assimilation, of motion, and of sense ; the individual 

 tendency, by the brain and osseous system. The degree of 

 development of these two antagonistic formative powers dis- 

 tinguishes in reality, and partly defines the varieties of the 

 human constitution. The first tendency to the formation of 

 bone in excess, is favoured by the newer formations from the 

 Jura limestone upwards, and so also is the tendency to 

 tubercular deposits. The second tendency occurs in the older 

 formations up to the Jura, and it predisposes to scrofula in 

 all its varieties. Dr. Escherich considers the formation of 

 urinary calculi to be a symptom of the former tendency, of 

 the phosphatic diathesis, as it were a complement to excessive 

 formation of bone. Excessive formation of bone diminishes 

 the activity of the kidneys, and sparing secretion of urine 

 favours the prevalence of lithic acid in the urine, which is 

 almost the invariable nucleus of urinary calculi. Lithiasis 

 and endemic tendency to tubercles, agree in geographical dis- 

 tribution, with this difference, that in the same district, the 

 first is found in only 1 per cent, of the inhabitants, while the 

 last occurs in 15 per cent. It is also much more easy to 

 counteract the tendency to stone (especially by drinking 

 abundantly,) than the other one. V. Walther's account of the 

 antagonistic action of the skin and kidneys agrees with these 

 views, as calculi and cutaneous eruptions do not occur toge- 

 ther^), which is explained by the co-existence of a thick, 

 strong epidermis with the tendency to formation of bone. 

 Further, in accordance with these views, is the fact in com- 

 parative anatomy, that almost all the rodentia, in whom the 

 osseous system predominates, for instance rats, have as a rule, 

 stone in the bladder. (Calculi have also been found in tor- 

 toises and in other chelonian reptiles.) 



But there is much difficulty in recognising lithiasis as a com- 

 plement of the osseous system, as a result of excessive forma- 



