KFFECTS Oy MAGNESIA ON URTC ACID. 
83 
and both the mucus and the sand were conside rably dimuiishcvi 
in quantity. In six weeks, the urine, when voided, was trans- 
parent ; but a considerable deposition of the phosphates took 
place, when it had remained some hours at rest. In this state 
he left London, and has since informed me, that the sediment 
gradually diminished under the usf of the carbonic acid, that 
his urine is never turbid, and that the irritation in the bladder 
has entirely subsided. 
It did not appear necessary to detail the minutiae of the above 
cases ; they have been selected with a view to elucidate the 
treatment of the disease, as far as it depends upon chemical 
principles, and to furnish the data upon which the following 
conclusions are founded. 
1. That where alkalies fail to relieve the increased secretion 
of uric acid, and to prevent its forming calculi in the kidneys, 
or where they disagree with the stomach, magnesia is gene- 
rally effectual, and that it may be persevered in for a conside- 
rable time without inconvenience, where the tendeni^ to form 
excesss of uric acid remains. 
2. When the alkalies, or magnesia, are improperly continued, 
after having relieved the symptoms connected with the forma- 
tion of the red sand, or uric acid, the urine acquires a tendency 
to deposit the white sand consisting of the amraoniaco-magne- 
sian phosphate and phosphate of lime. 
3. The mineral acids, (muriatic, sulphuric, and nitric) dimi- 
nish, or entirely prevent the deposition of the phosphates j but 
are apt to induce a return of the red gravel. 
4. That vegetable acids, especially the citric and tartaric, are 
less liable to produce the last mentioned effects, even when ta- 
ken in large doses for a long time ; and that carbonic acid is 
particularly useful in cases, where the irritable state of the 
bladder prevents the ejubition of other remedies. 
umniar\ . 
