24 STUDY OF DIATOMS. 



have undertaken his experiments with the most minute precautions, and 

 the curious nature of the results which he has obtained render it advi- 

 sable that diatomists should make fresh researches in this direction, more 

 especially as Dr. Miquel asserts that his own experiments are not in 

 accordance with Messrs. Lockwood and Kitton's opinions. 



2. Study of Diatoms. 



In my treatise on the microscope (') 1 have given all the necessary infor- 

 mation about that instrument from the point of view of general micro- 

 scopy. For any details which do not specially concern diatoms reference 

 should be made to that work, and so I shall only give a few notes here 

 specially intended to assist diatomists. 



Workroom. The diatomist's workroom should not be very large ; the 

 essential is that it should, as far as possible, be free from dust ; it will 

 therefore be well not to encumber it with furniture or books in open 

 shelves, but to furnish it with glazed cases, where books, instruments, 

 and preparations may be kept. 



The study of diatoms sometimes requires the use of sunlight, and in 

 that case the room should be facing east or west. Professor Harting 

 recommends a southern situation. Although some authors condemn the 

 latter direction, we have found it excellent, and use it almost exclusively, 

 although we have windows with other aspects. 



The principal furniture of the workroom is the table. It should be 

 heavy, massive, and of such a height as to render it possible to work 

 conveniently when standing up. An easy position can be assumed with 

 a high chair, but this should only be used exceptionally. 



In addition to the workroom, the diatomist should have a room or 

 kind of laboratory where he can do all his dirty work, such as cleaning 

 diatoms, boiling in acids (which latter is best effected in a glass stink- 

 chamber, such as are used in chemical laboratories), developing photo- 

 graphic plates, &c. 



Artificial Illumination. In our climale the diatomist is frequently com- 

 pelled to employ artificial light. Nothing surpasses incandescent electric 

 light (-) which can be obtained at the present day in sufficient quantity 

 for microscopical research without much trouble and at small cost. In 



( ) The Microscope : its Construction and Management, by Dr. Henri Van Heurck. English 

 edition, translated by Wynne E. Baxter. London : Crosby Lockwood and Son, 1893. 



( 2 ) See H. Van Heurck L'Eclairage electrique applique' aux recherches de la micrographie, 

 2nd Edition in Pelletan's Journal de Micrographie ; Van Heurck's Microscope English Edition, 

 pp. 109-117. 



