1660 



Journal of Applied Microscopy 



now regularly made for use with the most improved microscopes. A camel's 

 hair brush was also considered a necessary auxilliary, as were needles mounted 

 in wooden handles. 



An important part of Marshall's microscope for the examination of the blood 

 (1704) was a fish trough with glass bottom and metal sides. The small fish to 

 be examined was held quiet by a metal half-cylinder placed over it's body, and 

 from which the tail projected. 



Ellis's aquatic microscope (1755) was the precursor of the modern dissect- 

 ing stand, which it resembles very much in general appearance. The lens with 

 Lieberkuhn illuminator was carried on an adjustable arm. The stage was a 

 circular frame in which a transparent plain glass plate, with black spot, placed 

 eccentrically for use with opaque objects, or a thin watch-glass, could be placed. 

 A projection at the side of the stage supported a detachable stage forceps for 

 examining mineral or other solid objects on all sides, an accessory which might 

 well be adapted to our present dissecting stands. 



A microscopist at work. 



Martin's large microscope (1780) had a mechanical stage with rectangular 

 movements of great delicacy. An apparatus for holding " animalcules '' con- 

 sisted of a delicate open framework holding seven glass discs of various sizes, 

 each provided with a glass cover held in a metal ring pivoted at the side so that 

 the cover could be swung aside ; the fluid containing the organisms being held 

 between the two glass discs. This apparatus was attached to the stage when in 

 use, so that each cell could be brought under the objective. Martin's micro- 

 scope had no less than twenty-four objectives, all non-achromatic of course, 

 ranging in power from four inches focus to one-tenth of an inch, each of the 

 lower powers being supplied with a I^ieberkuhn. One of the accessories fur- 

 nished with Adam's Variable microscope (1771) was a hand magnifier, mounted 

 exactly as are the watchmaker loupes of to-day. 



On the whole, it may be said that the accessories of the early microscopists 

 were few in number, as were their requirements, but the elaborateness of mounting 

 and ornamentation would impress us at this time, when the microscope has 

 become an instrument of such practical utility, as extremely impractical. 



L .H. E. 



The writer has received much interesting information regarding old microscopes now in the 

 possession of individuals and institutions. Whe should he glad to have more, with photographs 

 of the instruments, for future use in the Joi rn.M.. 



