[ 455 ] 



XXXII. Experiments and Ohfervations on 

 the Waters of Buxton and Matlock, in 

 Derbyfhire, ^Thomas Percival, of Mzn~ 

 ehefterv M. D. and F. R. S. 



Readjune 2-j:, rpHE water of faint Ann's- well is 

 found, by analyfis, to contain cal- 

 careous earth, foffil- alkali, and fea falts ; but in 

 very fmall proportions : for a gallon of the water, 

 when evaporated, yields only twenty three, or twenty 

 four grains of fediment. It flrikes a light green 

 colour with fyrup of violets, fuffers no change from 

 an infufion of galls, from the fixed vegetable alkali, 

 or from the mineral acids ; becomes milky with the 

 volatile alkali, and with Saccharum Saturni; and lets 

 fall a precipitate on the addition of a few drops of 

 a folution of filver, in the nitrous acid. The fpecific 

 gravity of this water is precifely equal to that of rain, 

 water, when , their temperatures are the fame j but 

 it weighs four grains in a pint lighter, when firft 

 taken from the fpring, - The heat of the bath is 

 about 82 degrees of Fahrenheit's thermometer ; that of 

 Saint Ann's well, as it is a fmaller body of water, and 

 expofed to the open air, is fomewhat Jefs. The water 

 is tranfparent, fparkling, and highly grateful to the 

 palate *.. 



* I am indebted to the information of the worthy phyfician 

 who attends at Buxton, for fome of thefe fa£ts, 



In ; 



