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Practical Hints on the Manipulation of the Microscope 

 and a Description of its Parts. 



By Frederick Noad Clark. Read October 12th, 1905. 



In giving a few practical hints or instructions as to the use of the 

 modern microscope, I am doing so with a certain amount of diffi- 

 dence, feeling that to a large extent some members at least have as 

 good a knowledge of the subject as myself ; so that I must ask their 

 kind forbearance when I traverse well-beaten ground or weary them 

 with elementary details. By way of excuse I will just explain that I 

 consented to give this paper only by reason of the pressure put upon 

 me by our hard-working Secretary, Mr. Turner, who put it to me in 

 this way — that there are many of our members possessing a micro- 

 scope to whom a few hints on its use and a description of its parts 

 would be acceptable. I have also certainly noticed at many soirees 

 and microscopical evenings that the owner of a modern and costly 

 instrument, with elaborate accessories, is frequently at sea as to its 

 use and how to display his objects to the best advantage. 



There are, I imagine, few scientific instruments which require so 

 much explanation as to their construction and use as the microscope ; 

 indeed, the selection of an instrument from amongst the variety of 

 patterns obtaining must be a matter of some difficulty for even one 

 who is tolerably acquainted with its use. One may learn a good 

 deal from the finely illustrated catalogues of the various English and 

 continental makers, who also give an excellent description of the 

 various parts of the microscope and its accessories. For a more 

 thorough knowledge of the theory and practice of the instrument I 

 can recommend a study of that magnificent work " Carpenter on the 

 Microscope and its Revelations," edited by Dr. Dallinger, which has 

 reached its eighth edition, and is the most complete and up-to-date 

 work on the subject existing. 



It is perhaps unnecessary to remark that the cost of a serviceable 

 and reliable instrument varies in proportion to the requirements of 

 the purchaser as well as to the amount of money he intends to ex- 

 pend on its purchase ; but, broadly speaking, for any sum from ^5 

 t0 £s° ne can procure an instrument with which really good work 

 may be done. Below the smaller sum he could not rely on getting 

 an efficient instrument, although he might be fortunate enough to 

 obtain a second-hand one which would meet his requirements. 



The exact origin of the microscope is surrounded with much un- 

 certainty. By some writers it is considered probable that it was 

 known to the Greeks and Romans, no doubt in a very rudimentary 

 form. There is more definite information at hand that in the six- 



