86 HOW TO USE THE MICROSCOPE 



in a microscopic fitting ; they take the place of a 

 micro-objective, and are used without an eye-piece. 

 With long extension of bellows, they give magnifi- 

 cation of several diameters. These lenses have 

 hitherto been rather costly, but Messrs. Aldis 

 Brothers, Sparkhill, Birmingham, have recently put 

 one on the market at the remarkably low figure of 

 £1 10s. 6d. It is known as the " Aldis Anastigmat 

 for Photo-micrography." I have tested this lens 

 and find it excellent. 



APPENDIX 



The worker desirous of securing more advanced 

 guidance than is to be found in the simple instruc- 

 tions given on the foregoing pages will be well 

 advised to consult any of the following books : 



The Microscope and its Revelations, by W. B. Carpenter. Edited 

 by Dr. Dallinger. Churchill. 28s. This is the standard 

 work. 



A Popular Handbook to the Microscope, by Lewis Wright. Re- 

 ligious Tract Society. 2s. 6d. 



Modern Microscopy, by Cross and Cole. Fourth Edition, 1912. 

 Bailli^re, Tindall and Cox. 6s. 



Elementary Microscopy, by F. Shillington-Soales, 1905. 

 Bailliere, Tindall and Cox. 3s. 6d. 



Practical Microsco'py, by George E. Davis. Allen and Co., 

 1889. 7s. 6d. 



Practical Photo- Micrography, by A. Pringle. Iliffe. 3s. 6d. 



