SIR,
Your most obedient humble Servant,
John Pringle.
_Postscript to Dr._ Whytt’_s Observations on Lord_ Walpole’_s
Case_[201].
[Read Dec. 8, 1757.]
“I Do not know, if it be worth while to observe, that lately, in making
some experiments with different _calculi_, there was one almost as
white as chalk, but of a less hard substance than the others; and which
was not in the least degree dissolved or softned by being infused 20
days in oystershell lime-water, but yielded somewhat to a solution of
Spanish soap in common water.
From this experiment one may conclude, that it is better to prescribe
both soap and lime-water for the stone, than any one of them alone;
and that if one of these remedies has failed of giving relief, the
other ought to be tried: for as the above white _calculus_, which
yielded a little to the solution of soap, resisted lime-water; so there
may perhaps be others, that are readily dissolved by lime-water, but
little affected by soap.
Dr. Springsfeld’s experiments with lime-water are somehow not just; for
in several _calculi_ I have found the dissolving power of oystershell
lime-water above eight times greater than he makes it.”
_Some Observations on the lithontriptic Virtue of the_ Carlsbad
_Waters, Lime-water, and Soap: In a Letter to Dr._ John Pringle,
_F.R.S. from Dr._ Robert Whytt, _F.R.S. and Professor of Medicine in
the University of_ Edinburgh.
[Read Dec. 15, 1757.]