184 



Botanic Microscope, 



Art. IV. Description and Use of the Botanic Microscope, 



Description and Use of the Botanic Microscope. — Several readers hav- 

 ing expressed a wish that we should describe the use of a cheap microscope, 

 we give the following as the most suitable for general purposes : — a b 

 (^fig. 38.) is a pillar, which screws into the top of the box, containing the 

 whole of the apparatus. 

 s the stage for laying the 

 objects on; it slides up 

 and down the pillar, to 

 adjust the object which is 

 to be laid upon the stage, 

 to the focus of the' mag- 

 nifier c, three of which 

 belong to this micro- 

 scope. The knife g, 

 needle f and scissors /z, 

 ai'e used in dissecting or 

 separating the parts of 

 flowers, &c. e is a pair 

 of tongs for taking up 

 any small object, or 

 turning it about on the 

 stage. There is an ivory 

 plate fitted to the stage, 

 black on one side and 

 white on the other ; dark- 

 coloured objects should 

 be laid on the white 

 side, and vice versa. 



To use the Microscope. — When taken out of the box, slip on the stage ; 

 and having screwed the pillar into the top of the box, it is ready for use. 

 Lay the object on the stage, and slide it up and down till it appears per- 

 fectly distinct : as most persons' eyes differ, every one should adjust the 

 object to his own. The three magnifiers are of different foci, and may be 

 used separately, or either two of them together, or all three, by screwing 

 them one on the other, making, in this way, seven different powers. The 

 smallest magnifier has the largest aperture. When more than one is used, 

 the least magnifier, or that with the largest aperture, should be next the 

 object. Let as much light as possible fall on the object while under exa- 

 mination, particularly when the greater magnifying powers are used ; and be 

 attentive not to shade it with the hat, or other part of the di-ess. If this 

 precaution is not attended to, the objects will appear obscure ; this will 

 also be the case if the magnifiers are not quite clean. Wash-leather is 

 the best thing to wipe the glasses with, and a piece is put into the box for 

 that purpose. This microscope is not confined to the examination of bota- 

 nical subjects, but may be used for any kind of objects that can be laid on 

 the stage, such as speciiuens of minerals, seeds, shells, insects, &c. ; and, as 

 a contrast to these, artificial objects, as medals, coins, intaglios, cameos, fine 

 writing, printing, miniature-painting, and engraving ; silks, fine lace, linen, 

 watch-work; in short, any of the finest works of art. Price \2s. 



There are a variety of other microscopes, at various prices, up to 7 and 

 even 10 guineas, and we have seen one in the workshop of a celebrated 

 manufacturer at Munich, the price of which was 150 guineas. There are 

 also various magnifying glasses in use by naturalists, and especially by mine- 

 ralogists, at various prices, from 1^. Qd. upwards. A good plan for an in- 

 tending purchaser is to state his wants to a respectable tradesman, and be 

 ^ded in a great measure by his advice, — Cond. 



