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V M I CROSCOf I C A L 



Essays. 



the appearance from this fubftance, according as the time of the 

 application is nearer to or more diflant from that in which the 

 folution was made. 



Fig. 1, PI. XXXI. reprefents the microfcopical cryftals of fait 

 of wormwood. The fhootings from the edges of this folution are 

 often very thick in proportion to their length, their fides full of 

 notches, the ends generally acute ; many fpear-Iike forms are 

 alfo -to be obferved, as well as little cryftals of a -variety of 

 figures. 



Fig. 2, Plate XXXI. the fait of amber. The fhootings of this 

 fait are highly entertaining, though the procefs is very flow ; many 

 fpicula moot from the edge towards the middle of the folution, 

 and from the pointed ends of the fpicula, a great variety of diver* 

 fified branches may be obferved, varioufly divided and fubdivided, 

 and forming at laft, fays Mr. Baker, a winter fcene of trees with- 

 out leaves. 



Salt of hartihorn, Fig. 3, Plate XXXI. This fait moots out 

 from the edge of the drop into folid, thick, and rather opake 

 figures ; from thefe it often moots into branches of a rugged ap- 

 pearance, fimilar to thofe of fome fpecies of coral. 



Fig. 4, PI. XXXI. reprefents the configurations of fal ammoniac. 

 Thefe form a molt beautiful objecl in the microfcope : a general 

 idea may be more eafily formed, by confidering the figure here 

 exhibited, than by any verbal defcriptioru 



A COM- 



