Ml CROSCOPICAL 



ESS A YS. 



l 59 



vials of fpirit of wine. Nothing but fpirit of wine can preferve 

 thefe tender bodies. 



To PREPARE THE RlND FOR OBSERVATION. 



As the veflels of the rind are of different diameters in various 

 trees, though their conltruction and that of the blebs is perfectly 

 the fame in all, it will be beft to chufe for this purpofe the rind 

 of a tree wherein they are largeft. The rind of the afh-leavcd 

 maple is finely mi ted. A piece of this may be obtained of two 

 inches long, and will very fuccefsfully anfwer the intention. Such 

 a piece being prepared without alum or fpirit, but dried from the 

 water in which it had been macerated, it is to be impregnated 

 with lead in the following manner, to mew the apertures by 

 their colour. 



Diffolve one dram of fugar of lead in an ounce and a half of 

 water; filter this through paper, and pour it into a tea-cup. 

 Clip off a thin flice of what was the lower end of the piece of 

 rind as it grew on the tree, and plunge it near an inch deep into 

 the liquor ; keep it upright between two pieces of flick, fo that 

 one half or more may be above the water : whelm a wine and 

 water glafs over the tea-cup, and fet the whole in a warm place. 

 When it has Hood two days, take it out, and clip off all that part 

 which was in the liquor, and throw it away. 



The circumftances here mentioned, trivial as they feenx, muff 

 be attended to: the operation will not fucceed, even if the 

 covering- g lafs be omitted ; it keeps a moifl atmofphere about the 

 rind, and makes it's veflels fupple. 



While 



