PREFACE 



IN the following pages an attempt has been made to set 

 out the methods of obtaining photographs of microscopic 

 objects. It is not an easy matter to describe the details 

 and processes of a practical scientific subject in a lucid 

 and interesting manner: it is one thing to be conversant 

 with the practical side of the subject, but quite another 

 to write such a description of the procedure as will enable 

 another person to carry it out. In the present instance 

 all that is claimed is that the attempt is a straightforward 

 one, founded on practical experience. 



The description of instruments is as full as the circum- 

 stances would appear to justify ; that, for instance, of the 

 microscope, about which much can be learned from books 

 on pure microscopy, is less full than the description of 

 cameras and their construction. The number of references 

 to the work of others is small : not because the writer 

 wishes in any way to pass over such work or to minimise 

 its importance, but because the subject is one that is best 

 treated in the light of personal experience. 



Sincere thanks are due to Professor E. T. Hewlett, who, 

 in addition to reading the proofs and making valuable 

 suggestions thereon, has at all times given advice, and 

 placed at the author's disposal the benefit of his wide ex- 

 perience. Thanks are also due to Mr. F. Shillington Scales, 

 M.A. ; and to Mr. G. Beilby, F.K.S., and Mr. C. 0. Bannister 

 for the loan of blocks and specimens. Particularly, also, 

 should be mentioned the author's indebtedness to Mr. 

 Conrad Beck, whose Cantor lectures on * The Theory of 



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