62 PHILOSOPHICAL TRANSACTIONS. [aNNO l7Qi- 



These 6 were separately taken out of the lixivium and put into a mortar, 

 and rubbed or broken, and then carefully returned to their separate phials, be- 

 fore the 2d addition of lixivium, in order to forward the solution. 



Spechnens described. — N° ] , The external part of a laminated calculus, of a 

 light yellowish brown colour.* — N° 2, The external part of a calculus, in colour 

 like dirty tobacco-pipe clay.-|- — N° 3, A light brown laminated calculus. — N° 4 

 and 5, two specimens from 1 calculus ; of which N" 4 is the external coat, of a 

 dirty tobacco-pipe clay colour. — N° 5, the internal part of N° 4, yellowish like 

 ]S[° ] . — N° 6, a calculus taken out of the urethra ; a greyish white, inclining to 

 yellow, of a porous texture — N" 7, a calculus about the size of a nutmeg, 

 taken from a child of a year old, given by the late Mr. Pott ; ash-coloured, in 

 waves of difierent shades, laminated and hard. — N° 8, a dark brown very hard 

 calculus, of the mulberry kind. — N° Q and 10, two specimens from one calcu- 

 lus; of which N° 9 is the external whitish part, which appeared like a coat of 

 calcareous earth, covering an irregular mulberry calculus.;}: — N° 10, the brown 

 mulberry part covered by N*^ Q. The 3 following are parts of one large, lami- 

 nated calculus ; of which N° 1 1 is the external lamina, of a brownish yellow. — 

 N° 12, the central part, called the nucleus, of a pale orange colour. — N° 13, 

 some of the laminae, between the nucleus and the external coat, of a sparkling 

 appearance. — N° 14 a whitish, porous, and easily broken calculus. 



The experiments by fire explain the unequal accounts of authors, respecting 

 the component parts of calculi. In general, those which contain the largest 

 proportion of volatile parts were most soluble in lixivium. The insolubility of 

 some explains the want of success in several cases, where lixivium, soap, and 

 lime-water, have been given as remedies. The solubility of others, joined with 

 the testimony of reputable authors, and Mr. L.'s experience for near 30 years, 

 confirm the salutary effects of lixivium in many cases. It frequently happens, 

 in fits of the gravel and stone, that gravel or small pieces of calculi are dis- 

 charged, which should be examined. If perfectly soluble in lixivium (Aq. kali 

 puri,) the remedy is obvious ; if imperfectly, doubtful ; if insoluble, lixivium 

 will only irritate, without benefit. 



JiF'. Chermes Lacca. By William Roxburgh, M. D., of Samulcolta. p. 228. 

 Some pieces of very fresh looking lac, adhering to small branches of mimosa 



* The nucleus, so called, being tlie central part, was of a much deeper colour, and liad been 

 found not so soluble in lixivium as the light brown part. — Orig. 



+ The nucleus was of a bright yellow, and more soluble in lixivium than the whitish part. — Orig. 



X The covering of this calculus induced a suspicion that lime or lime-water might have been taken, 

 and, by being decompounded by fresh urine, containing fixed air, form this covering. Other cal- 

 culi have afforded the same suspicions. 



In future, an account of medicines taken might afford much information, joined wiUi tlie exami- 

 nation of different parts of large calculi taken out of tlie bladder. — Orig. 



