294 THE USE OF THE MICROSCOPE 



3G. ■- — . 1925. Photographing chromosomes, Ji)iir. Hoy. Micr. 



Soc, 445-446. (Use of the Phoku apparatus.) 



37. Berek, M. 1920. (On the characteristic constants of microscope 

 objectives.) Zeit. tviss. Mikrosk. 



37o. — ■ — ■ — •. 1920. Die Scharfentiefe des Mikroskops, Zeit. wiss. 

 Mikrosk, 37: 120. 



38. . 1921. tiber selektive Beugung im Dunkelfeld und 



farbige Dunkelfeldbeleuchtung, Zeit. ^oiss. Mikrosk, 38: 237-257. 

 (Important for visibihty.) 



38«. . 1923. Zur Theorie der Spiegelkondensoren ftir Dunkel- 

 feldbeleuchtung und Ultramikroskopie, Zeit. wiss. Mikrosk., 

 40 : 225. 



39. . 1924, Betrachtungen zur Darstellung des Abbildungs- 



vorganges im Mikroskop, Zeit. loiss. Mikrosk., 41: 1-15. (An 

 excellent account.) 



40. BoEGEHOLD, H., and A. Kohler. 1922. Das Homal, ein System, 

 welches das mikrophotographische Bild ebnet, Zeit. wiss. Mikrosk., 

 39 : 249-262. (Account of the new projection lens.) 



41. Boegehold, H. 1924. DieLupe. Das zusammengesetzte Mikro- 

 skop. Grundziige der Theorie der optischen Instrumente, 359-505. 

 Czapski-Eppenstein, Leipzig. (Czapski's original account, twice 

 revised. An excellent short treatise on lens and microscope.) 



42. Carpenter, W. B. 1875. The microscope and its revelations, 

 London. (A classical work, readable today.) 



43 . and D allinger. 1901 . The microscope and its revelations. 



Vol. I, London. (Rather out of date, but gives a good account of 

 the diffraction theory.) 



44. Chance Brothers. 1923. Contrast filters, Jour. Roxj. Micr. Soc, 

 371. (New glass color screens.) 



45. Coles, A. C. 1915. An easy method of detecting Spirochseta 

 pallida, and other spirochsetes, Brit. Med. Jour. (Dark field with 

 dry stained objects.) 



46. — ■ — ■ — ■. 1922. Critical microscopy, London. (An excellent book, 



describing a new method.) 



47. . 1926. The star test for microscopic objectives, Watson's 



Micr. Rec. 7: 16-19. (Probably the best test known.) 



47a. — ■ — — . 1927. Relief staining of bacteria, protozoa, infusoria, 

 Watson's Micr. Rec, 10: 23-25. (An important method.) 



48. CoNRADY, A. E. 1904. Theories of microscopical vision. Jour. 

 Roy. Micr. Soc, 610-633. (Excellent account of the diffraction 

 theory.) 



49. — — ■ — ■. 1905. Theories of microscopical vision, Jour. Roy. Micr. 



Soc, 541-553. (A continuation of the foregoing paper.) 



50. — ■ . 1912. (On dark-ground illumination.) Jour. Quekett 



Micr. Club, 475-480. 



