1888.] MICROSCOPICAL JOURNAL. 107 



Notes from a Foreign Land. 



By ROMYN HITCHCOCK. 



A large number of subscribers who have requested microscopic specimens 

 from Japan have not yet received them. The reason is that I have not yet 

 been able to collect a sufficient quantity of really good material to supply the 

 demand. Probably none will be sent before next summer, when I hope to 

 find an abundance of fine diatomaceous material in the course of mv travels 

 in the north of Japan. ' 



There is a decided eftbrt likely to be made to secure the admission of micro- 

 scopes and other apparatus free of duty. I do not know just what position 

 the Editor will assume in this matter, but it is very certain that there is much 

 to be said on both sides of the question, and that the editorial views of every 

 special journal will carry much weight. I can readily conceive that both sides 

 would do well to urge their claims, for I really believe the movement on foot 

 may result in a great reduction, if not the abolition, of custom duties on 

 microscopes. 



Photography offers but few novelties of interest to microscopists. Mr. 

 Walmsley has lately made a demonstration of the value of ortho-chromatic 

 plates in photo-micrography in Philadelphia, as I leai'n from the photographic 

 journals. It is quite likely that such plates will prove of great advantage in 

 photographing many specimens, particularly such as have much red or yellow 

 in them. But those who for any reason cannot get the plates will find that a 

 yellow glass interposed in the path of the light will greatly improve the re- 

 sults with such objects. The glass may be placed in anv position, but probably 

 the most convenient will be beneath the stage, or below the condenser. The 

 action of the colored glass is to absorb the strongly actinic light, the blue and 

 violet, thus lengthening the time of exposure and allowing the yello\v rays a 

 longer time to act upon the plate. The yellow light thus becomes more active 

 relatively to the blue, and details in yellow parts of the specimen are brought 

 out which would be invisible in a photograph taken in the usual manner. 



A good substitute for yellow glass can easilv be made by getting some plain 

 collodion from a photographer and coloring it with yellow aniline. The depth 

 of color can be varied, and it is w^ell to have several shades to suit dift'erent 

 objects. Aurantia is a good coloring matter for this purpose, recommended 

 by Dr. Vogel. Use about five grains to two ounces of collodion. The yel- 

 low collodion is flowed over glass plates, an operation that may well be en- 

 trusted to a ^photographer, and afterwards varnished to protect the film. An 

 alcoholic extract of turmeric may also be used in the same manner, and tur- 

 meric can always be found in drug stores. 



Exposures with such color screens must be much prolonged, even as much 

 as from five to ten times what would otherwise be required. 



There have been various new devices for cameras to be used with the micro- 

 scope figured in various journals, but the one that most highly commends 

 itself, from the description in the Journ. Royal Micr. Soc. of December, 

 is that of Mr. E. M. Nelson and Mr. C. L. Curties. It is made of two long, 

 square card-board tubes, one sliding into the other. The microscope with its 

 tube horizontal is placed in position on the base board, the object focused by 

 the eye, the front card-board tube then pushed into position, and the projecting 

 eye-piece used for the final focusing ontthe glass. It seems an excellent plan 

 to be able to push the front of the camera back from the microscope far enough 

 to get the head down to the microscope. 



There may be something useful in- the recent observations of Mr. Francis, 

 ot .Sydney, Mr. G. D. Hirst, and Mr. E- M. Nelson concerning the increased 



