212 DR. BENCE JONES ON THE SOLUTION OF EARTHY CALCULI 
The action began at 9^ 30 “a.m. and was continued until 1 p.m., the temperature 
being between 66° and 106°. 
The action recommenced at 2 p.m. and was continued until 4 p.m., the temperature 
being between 70° and 108°. 
The total time was .5 ■, i ifu 
The piece of marble when dry weighed 142^ grains, so that m five and a half hours 
271 grains were dissolved. The solution became slightly alkaline ; the marble was 
dissolved at the part in contact with the positive electrode. See fig. o. 
Experiment 4.— Another mass of marble, with the same battery, was tned in a so u- 
tion of sulphate of soda, specific gravity about 1034. 
The action began at O'* 30 ”a.m. and was continued until 1 p.m., the temperature 
being between 87° and 100 . . 1 ^ * 
The action recommenced at 2 p.m. and was continued until 5 p.m., the temperature 
being between 100° and 106 . 
The total time was 6^^ . 1 u' 
When the marble was dry it weighed 156^ grains. Hence in six hours and a halt 
only H grains of marble were dissolved. See fig. 6. 
Without doubt the difficult solubility of the sulphate of lime was the cause that 
hindered the solution of the marble. , . 
The contrast between the solution of nitre and the solution of Glauber-salt is terv 
remarkable ; the former being seven and a quarter times more efficacious than the 
Icitrtcr 
The result of these experiments on the earthy phosphates and carbonate of lime 
may be thus arranged; — 
h m 
Exp. 1 lasted 7 15 in nitre solution . . • 
Exp. 2 lasted 1 13 in nitre solution . . • 
Exp. 3 lasted 5 30 in nitre solution . . . 
Exp. 4 lasted 6 30 in Glauber-salt 101 
Hence it is evident that calculi consisting of the earthy phosphates or of carbonate 
of lime can be most rapidly dissolved in a nearly neutral dilute solution of nitre, at 
the temperature of the human body, by the aid of the galvanic battery. 
Average temp. 
Pairs of 
plates. 
Grs. dissolved. 
. . 102° 
10 
15 
. . 96 
20 
31 
. . 104 
10 
27^ 
. . 101 
10 
Conclusions. 
Thus then, by the aid of electricity, from 2 to 9 grains of uric acid calculi can be 
dissolved in an hour, whilst in the same time from 2 to 25 grains of phosphatic 
calculi can be dissolved in a neutral dilute solution of nitre at the temperature ot 
the body However, only from half a grain to 2 grains of oxalate of lime can he 
removed by the same means in the same time. Still, if the stone consists of oxa ate 
with urate, from 1 to 2 grains may be dissolved in an hour ; and if it consist of oxalate 
with phosphate, from 4i to 5i grains can be taken away in an hour. 
