AND ON THE INTRODUCTION OF DECOMPONENTS INTO THE BLADDER. 9 
proved to me the efficacy of cider, as an ordinary drink, in cases of phosphatic urinary 
deposit accompanying - rickets, and diseases of the lumbar vertebrae. 
From these circumstances I was inclined to believe, that although the acetate had 
failed, a malate or super-malate of lead would be likely to act as a decomponent of 
phosphatic concretions. Another reason for selecting- malic acid was the solubility 
of the salts it forms with the bases of these calculi, viz. magnesia, lime, &c. Having 
no readier means of procuring the malate, I sought to prepare it from cider vinegar, 
or what is called cidre-aigre in contra-distinction to vin-aigre, a liquid commonly 
used as a substitute for wine or malt-vinegar, in the farm-houses and cottages of the 
Channel Islands. 
To this cidre-aigre a watery solution of neutral acetate of lead was added, till pre- 
cipitation no longer took place. The liquid, on being filtered, was clear, devoid of 
acidity or acrimony; and, as Dr. Christison states, with respect to acescent wines 
to which lead has been added, it possessed “ a very pleasant sweetness, quite unmin- 
gled with metallic astringency*.” 
The whole of the passage, relating to French wines, from which the above sentence 
is quoted, seems particularly applicable to the liquid under consideration. In de- 
fault, however, of any authentic analysis of cider-vinegar, my observations induced 
me to believe, that the acids it contained were the acetic, malic, and tartaric ; but as 
I was unwilling to interrupt the course of experiments, in order to analyse it, I am 
unable to determine this point with the necessary accuracy. 
Nevertheless, whatever may be its composition, the immersion of fragments of 
phosphatic calculi in the liquid formed as before stated, was followed by very stri- 
king results : rapid chemical action ensued, visible to the naked eye ; when viewed 
by means of a low microscopic power, vehement decomposing action was manifest, 
the calculous particles becoming surrounded by areolae or nebulae of white sediment, 
which continued increasing until each fragment was reduced to a pulpy state resem- 
bling mortar, perfectly soluble in very dilute nitric acid. 
On suspending a fragment of fusible calculus, by means of horse-hair, in a test- 
glass containing the fluid, it became at once involved in a white cloud, from which 
a continuous stream of precipitate gravitated to the bottom of the glass. After the 
lapse of half an hour the calculus was found to have lost weight. This was an import- 
ant fact, without which it might have been supposed that decomposition of the solu- 
tion alone had given rise to the precipitate. 
Being inclined to doubt the evidence of my senses, rather than arrive at a false 
conclusion, I repeated the experiment. Another particle of triple phosphate was 
placed in a fresh quantity of the liquid ; at the moment of immersion chemical action 
commenced, and pursued the same course, until the fragment became a semi-solid 
mass, readily disintegrated. After a time nothing remained but the shreds of mucus, 
or other animal matter, which had cemented the earthy ingredients together. 
The result of analogous experiments, performed subsequently, warrants me in sta- 
* Christison on Poisons, p. 407. 
MDCCCXLlir. 
c 
