( 31 ) 



pretended experience of the efTedls of certain 

 flony waters in breeding the flone, may, upon the 

 bed authorities, be rejeded as falfe*. 



The befl way of determing the hardnefs or 

 fofrnefs of water, is by fcraping any certain quan- 

 tity of foap into It, and obfervlng how it dilTolves 

 or lathers. If water be perfectly foft, the foap 

 will diflblve quickly, uniformly, and without 

 curdling ; and, upon fhaking the glafs brifkly, 

 will raife a ftrong froth or lather at the top. But 

 the fmallefl degree of hardnefs will fhew itf^lf, 

 cither by the foap not diflblving fo readily, by its 

 turning curdly and uneven, or by lefs froth re- 

 maining after it is agitated 3 and the different de- 

 grees of hardnefs may hereby be very well deter- 

 'm,ined. The beft v/ay of making this trial is 

 with a fmall quantity of Caftile foap, viz. about a 

 grain to an ounce of water. 



RAIN-WATER. 



In fummer-time rain-water brings along with 

 it the feeds and embryos of vci^etables and ani- 

 mal cu la, 



t Medical Tranf, by the Coll. QfVhyf. vol. i. p. 7. 



