HARDWICKE'S SCIENCE-GOSSIP. 



265 



DRAWING FROM THE MICROSCOPE. 



By E. T. D. 



HE adaptability of 

 the neutral tint 

 reflector, as an 

 instrument of pre- 

 cision for drawing 

 purposes, com- 

 pared with the 

 camera lucida, 

 seems a trivial 

 matter for discus- 

 sion. But it would 

 be a source of re- 

 gret if a palpable 

 error were re- 

 corded in the 

 pages of Science- 

 Gossip, a periodi- 

 cal aiming at exact 

 information, and 

 the educational 

 and scientific in- 

 struction of many young microscopists with artistic 

 tastes. Mr. Bernard Hobson in the September 

 number commenting on the "hastily condemned 

 appliance," the neutral tint reflector, as a drawing 

 accessory, states that its radical defect of ' ' in- 

 version " may be overcome by a semi-rotation of 

 the object itself on the stage of the microscope, 

 which would assist the after drawing of details 

 without difficulty. To prove the fallacy of this 

 remedy, it may be necessary to recapitulate some 

 previous statements. For drawing, or rather, fixing 

 lines involved in an elaborate microscopic object, 

 the improved Wollaston camera lucida is the only 

 instrument ; a cheaper and handier form of lucida, 

 for certain purposes, is the tinted glass reflector ; but 

 its capabilities are so extremely limited, that all after 

 work, pursued direct from the microscope, either in 

 line, colour, or shadow, is frustrated by the " in- 

 version " of the picture, which no arrangement of the 

 object on the stage can obviate or overcome ; even the 

 practised artist is thus fairly bewildered in following 

 No. 228. — December 1883. 



up a drawing under such circumstances ; the trouble 

 is exactly tantamount to painting a landscape from 

 Nature, not only upside down, but when placed as it 

 should appear with the right turned over to the left ; 

 the neutral tint reflector effects this inversion by having 

 only one reflecting surface. Mr. Hobson says on 

 page 195, that it is perfectly obvious a semi-rotation 

 of the stage carrying the object will put the matter 

 right. The impossibility of this is demonstrated by 

 the following simple diagram. 



It is clear, that the semi-rotation of the object, fig. 

 166 (1) will place it in the position of (4) ; (3) is a 

 representation of (1) as drawn with the neutral 

 glass reflector. The problem is : to finish the draw- 

 ing (3) from direct observation of either (1) or (4), 

 and to fill in details of an involved object under 

 such circumstances (say, a section of injected lung) 

 with reflected light, is simply insuperable ; but, to 

 place the matter beyond all dispute, take the 

 impression of a sixpence turned over on the surface 

 (not rubbed from beneath) of a piece of soft paper , 

 such an impress would represent its contours as 

 sketched by the neutral tint reflector ; no rotation or 

 any arrangement of the coin would make its appear- 

 ance coincident with the impression. To afterwards 

 copy with scrupulous accuracy the details would be, 

 to say the least, a great trouble, immeasurably 

 increased, supposing the object involved a mass of 

 complicated structure. It may be generally insisted 

 that all mechanical aids in drawing should be 

 avoided, beyond the point of saving time. The 

 ultimate result of artistic and graphic representation 

 is the outcome of close and sensitive observation, 

 which cannot be helped by elaborate, or any ap- 

 paratus whatever. Such an arrangement as specified 

 by Mr. Hobson in his paper, clever and ingenious 

 as it may be, is not equivalent to, and can never 

 take the place of, the practised eye and the reliable 

 hand. There is an "abandon," a "go," in fine art 

 results, which no mechanical appliance or aid can 

 assist. In microscopical work the camera lucida 

 is merely a preliminary adjunct of limited utility in 



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