Martini LiHer c S, R. Lond* 
De FoNTIBUS MeDICATIS ANGLIiE. 
Exercitatio nova ^ prior, EboracL i6%2jnZ^* 
THe moft rational way (in the Opinion of thi^ curious 
and judicious Author) certainly to know what the 
Sahne Content^ to be found in the feveral Waters in Eng^ 
landyZre/is to Cryftallize them. 
This Griftallization is to be done with great care and 
Acctiratenefs;» not at once in a Lump, asitfeemsmoft 
have been fatisfied withi But after many Experiments, Ab- 
lutions, .Diffolutions and Shootings till you ^ have the 
whole Mafs of Salt fairly and fingly criftallized. 
Then to compare thefe Cryftals^with the Cryftals of all 
the known fofEle Salts^ to which end thefe known Salts al- 
fo are to be exactly defcribed from their faireft Cryftals.- 
All which he hath carefully done, defcribed^ and figured. 
But if it (hall be asked why fo many figures of the Salt 
of Nitrum Calcariumi and but one of the reft^tisanfwerdj» 
not that he judges thefe different fpecies , but only he 
gives moft of the Varieties, in which it is wont to fhoot ; 
not but that all the reft of the kinds of the figured Saks 
give as great a variety of Cryftals , but he thought them 
well enough known, that he might fpare himfelf the trou* 
ble and that it would be fufBcient to give the Compleateft. 
Nov/^ amongft the Saline Contents otall the Medicinal 
Waters which he hath either tryed or read of, he finds 
only two ; vi\. The Cryftals of a certain niter of an un- 
common figure and of common Salt , and thefe two on- 
ly not queftioning* but that there may be Waters in 
whi<:h «iatnrally hold others > but he hath not 
been fo happy as to meet with them * no not in thofe ve- 
H z ry 
