DESCRIFriON OF THK ACHROMATIC MICROSCOPE. 121 



SECT. 6. Apparatus for dissecting. Since the days of 

 Lyouet and Swammerdaii), until of late, very little pro- 

 gress has been made towards producing a microscope of 

 a more complete description than their's, for the purpose 

 of dissecting. It is true that two or three of this sort 

 have been constructed, but then they have been suited 

 for only one particular class of objects, such as the ele- 

 mentary tissues of plants, &c. Dr. Goring's engiscope, 

 with the additions hereafter mentioned as belonging to 

 myo wn microscope, probably approaches the nearest of 

 any to an efficient dissecting microscope ; nevertheless, 

 a still further advantage may be derived from having a 

 separate stand of proper dimensions made expressly for 

 the purpose. As one set of magnifiers will of course 

 suffice for both stands, the expense will not be consi- 

 derable. The microscope described in this chapter, with 

 the dissecting apparatus attached to it, is, I conceive, as 

 complete as any one of that size can be rendered ; its 

 dimensions however, are barely sufficient for the dis- 

 secting of large objects. 



Having alluded to Swammerdam's microscope, it may 

 be advisable, I think, before describing my own appa- 

 ratus, to refer the reader to an account of his method of 

 proceeding (as given in the Appendix) ; containing, as 

 it does, many useful remarks. After the perusal of this, 

 and a brief description of Lyonet's dissecting micro- 

 scope, the reader will be fully prepared to understand 

 the construction I have adopted. 



Lyonet's dissecting microscope may be thus de- 



