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feels instinctively that it is the work of the draughtsman, and not of Nature. 

 Of course, to overcome these difficulties, and give a natural representation 

 by photography of objects that have various focal planes, is exceptionally 

 difficult, for opticians have not yet given us object glasses that will show 

 even moderately deep objects in a fairly sharp-all-over focus; and any 

 lantern slide showing an object sharp in one plane, and blurred out of focus 

 in the rest, is. of course, utterly valueless. Now that the optical lantern is 

 coming so much more into use as an educational accessory, as so many can 

 at one time and so effectively be taught by its aid, I cannot but think that a 

 series of photo-micrographs, adequately exhibiting the wonders of Nature 

 in her minute conditions, must be of great value educationally. Drawings 

 and diagrams, however accurate, have not that hold upon the imagination 

 and memory, especially in the young and untrained mind, that a forcible 

 and truthful photo-micrograph direct from Nature would have, provided 

 always that such photographs are the very best that the process can 

 be made to yield, and what that best is has not been demonstrated yet. 

 The objects that pleased most on Wednesday at the " Royal " were those 

 in the neglected fields of illumination by spot lens or reflected light. When 

 some years ago I began this fascinating work, I was somewhat discouraged 

 by finding all the authorities on the subject agree in saying that no good 

 work had been, or could be expected to be, dono in these directions, from the 

 great and inherent difficulties to be overcome. As, however, the objects I 

 most wanted photographs of were in these classes, I determined to try and 

 disprove this opinion of the experts ; with what success I shall leave you 

 to decide ; perfection is by no means claimed for these slides, but they 

 are shown as evidence of what can be done in the valuable field of 

 photo-micrography. Allowance must be made for the amount of mag- 

 nification, which varies from 480 diameters in the lowest to 29,100 

 in the highest. With regard to some of the slides, I do not think they 

 could be improved upon, but in this matter I am like the Scotsman 

 who was perfectly willing to be convinced, but added : " Show me the mon 

 that can convince me ! " I really am very desirous of seeing better slides. 

 They have all been taken with the usual microscope accessories, in all 

 cases using the A eyepiece ; the O.G.'s were- of the finest quality, but not 

 specially corrected for this purpose, and no account has ever been taken of 

 the difference between the visual and actinic foci. What success I have 

 achieved has been mainly due to exceeding great care in the quality and 

 quantity of the illumination, using the ordinary oil lamp and bullseye 

 condenser ; and to a constant resolve to be satisfied with nothing that did 

 not do full justice to the object as seen at its ideal best under the micro- 

 scope ; also to be content with nothing that seemed capable m the least 

 degree of improvement. The photographic image has in no way been 

 " retouched " on the negative ; the only treatment the negative has under- 

 gone in some few instances has been the legitimate one of removing 1 

 dirt marks, etc., arising from imperfection in the micro mount, these 

 being necessarily photographed with the object; and an absolutely clean 

 micro mount, it will be admitted, is not a common thing. 



