214 
DR. BENCE JONES ON THE SOLUTION OF URIC ACID ANO 
Appendix to a paper on the Solution of Urinary Calculi in dilute Neutral Solutions, 
hy the aid of Electricity. 
By Henry Bence Jones, M.D., F.R.S., Physician to St. George's Hospital. 
Received December 18, 1852. 
Since the original paper was communicated to the Royal Society, it has appeared 
to me desirable to try whether more dilute solutions of nitrate of potash would have 
sufficient effect, when the strength of the battery and all other circumstances were 
the same as in the previous experiments. r • 
The solution of nitre was therefore made to contain only 10 grains of nitre to an 
ounce of water ; it had a specific gravity of 1015. Two ounces of urine were added 
to three pints of the nitre solution. 
A fusible calculus, weighing when dry 352 grains, was placed in this solution 
between the electrodes of twenty pairs of Grove’s plates. ^ ^ ^ 
The action commenced at 9** 20“ a.m., the temperature being ^>0 . 
The action was stopped at 12^ 45“ a.m., the temperature being 98 , so that the 
total time was 3^ 23“. The calculus when dry weighed 324 grains, so that the total 
loss was 67 grains. See fig. 7- . i j • fc 
Hence a solution of nitre of one-half the strength of that previously used is suffi- 
cient when decomposed to dissolve a fusible calculus at the rate of 19 grams an 
In order to observe the effect of reducing the strength of the battery when a dilute 
solution of nitre was employed, another calculus, consisting externally of phosphates, 
was placed in a solution of nitre, specific gravity 1015, and this was decomposed by 
ten pairs of Grove’s plates. 
The weight of the calculus when dry was 217 grains. 
The action began at 9 a.m., the temperature then being 50°; at 12*^ 4o“am. the 
action was stopped, the temperature being 98°. 
The action was recommenced at 2 p.m., temperature 60°. 
It was finally stopped at 4'' 45“ p.m., temperature 98°. 
The total time was 6’' 30“. The solution of nitre did not require to be changed 
during the whole time, the temperature remaining constant. After being acted on, 
the calculus when dry weighed 197 grains, so that the total loss was 20 grains. 
Hence in twice the time not one-third of the effect shown in the previous experi- 
ment was obtained, though this was chiefly owing to the diminished power of the 
battery, yet the greater hardness of the calculus used in this last experiment no doubt 
influenced the result. 
I then proceeded to try the effect of the dilute solution of nitre on a uric acid 
calculus. 
