48 SOME NOTES ON THE HISTORY AND DESIGN 



eye-piece end of the microscope being insetted through a circular hole 

 in the wall of the dark-room, aud the Daguerreotype plate, or the 

 wet collodion plate placed upon a board in the dark-room, on which 

 the image formed by the microscope had previously been focussed. 

 Considerable difficulties had to be overcome in obtaining the correct 

 adjustment that would yield a sharp, crisp image, owing to the, at 

 that time, imperfect corrections of microscope objectives; but 

 gradually from such crude beginnings the practice of photomicro- 

 graphy has attained to its present high standard of technique. That 

 the rapid improvement and high standard of perfection to which 

 microscope objectives, eye-pieces, and substage condeinsers have leached 

 are largely due to the investigations and labours of Abbe, Schott, 

 and Zeiss, all microscopists will readily admit; but that is about all, 

 though admittedly it is a very important contribution, that can 

 honestly be claimed by Germany as her share towards the perfection 

 of photomicrography. 



I know that opinions are very sharply divided on the subject ot 

 the microscope stand as made by British and German manufacturers, 

 and I feel that much of the criticism that has been levelled at the 

 British manufacturers is grossly unfair and inaccurate, because in 

 nine cases out of ten the would-be critic is already prejudiced in 

 favour of the German, has not a thorough technical knowledge or 

 experience, and frequently has never used a really first-class British 

 stand. I am quite ready to admit that the British maker has turned 

 out some very poor models, but so has the German; but because 

 the Britisher has producfeid some cheap models of poor quality, surely 

 that is no reason for damning at sight everything he produces. You 

 are not going to encourage home enterprise or industry by such 

 methods. I have now used the microscope practically daily for over 

 thirty years in my biological investigations, and during that time 

 models by all the leading British and Continental manufacturers have 

 passed through my hands, and have been, I hope and believe, 

 honestly, critically, and impartially tested. Out of that long experi- 

 ence I am bound to say that for comfort in working, rigidity, and 

 perfection in design and workmanship, I have yet to see the German 

 or Continental model that will touch the very best productions of our 

 leading British manufacturers. In no branch of microscopy is the 

 superiority of the first-class British microscope stand more readily 

 demonstrated and realised than in critical high-power photomicro- 

 graphy, for to produce the best results, rigidity, whether in the 

 vertical or horizontal position of the microscope body, and ease of. 

 manipulation of the mechanism of the substage and the top or 

 object stage are factors of vital importance — factors which are not 

 present in the horseshoe foot, or the finicky studs and knobs provided 

 for the adjustment of substage and substage-condenser, and mech- 

 anical stage, in the German models. Even the large Zeiss model 

 specially designed by that firm for photomicrography, though of good 

 workmanship, suffers from these inherent defects of the Continental 

 model, its substage mechanism being very cramped, and the mech- 

 anical stage provided with wretchedly small pinion heads. 



The microscope stand intended for critical photomicrography and 

 orisfinal research should have a solidly cast broad tri]:)od foot, such 

 as is present in the large research model of Swift, the R.M.S- model 



