DEDICATION. J* 
Purity o^many fimple Subftances and 
Compofitions made ufe of in MedL 
cine, and detedt Fraud and ImpofU 
tion. 
The minute living Animals exhi¬ 
bited in the Second Part of this Work, 
will excite a confiderate Mind to ad¬ 
mire in how fmall a Com oafs Life 
can be contained, what various Or¬ 
gans it can adtuate, and by what dif¬ 
ferent Means it can fubfift. They 
will alfo fhew that the Hand which 
made them is not confined to Size or 
Form; and that it has not been 
wanting to beftow on Creatures al~ 
moft invisible, and feemingly incon- 
fiderable, every Member and Faculty 
convenient to their Happinefs.—But 
this is an endlefs Subjedt, with which 
I fhall detain you no longer, than to 
pbferye, that were there wanting 
Proof§ 
