I. MICROSCOPES. 773 



359O. Solar Microscope. Laurent. 



3590a. Dr. Lionel Beale's Portable Microscope. 



Thomas. Hawhsley. 



(c.) ACCESSORY APPARATUS. 



3592. Microscopic Apparatus. Series of the more im- 

 portant pieces of apparatus and object glasses now supplied for 

 use with the microscope. R. fy J. Beck. 



3593. Object Glasses (4), showing the lenses before they 

 are put into the cells. It. fy J. Beck. 



3593a. New Stand on the Continental Model, the 



diaphragm being provided with centering screws so that it can be 

 adjusted to each objective as applied. Henry Crouch. 



3593b. Microscope Objectives and accessory Appara- 

 tus. Hiwy Crouch. 



Suited to the stand described above, and for microscopic work generally, and 

 mounting apparatus and materials. 



3594. Object Glasses, Apparatus, and Accessories used 

 in the different branches of microscopical research. 



M. Pillischer. 



3595. Microscope Lamp. M. Pillischer. 

 3595a. Fittings for Microscope. M. Lutz, Paris. 



3596. Apparatus to be used with the Microscope, for 



securing perfectly central illumination, manufactured by Wood 

 of Liverpool. Rev. W. H. Dallinger, F.R.M.S. 



The object of the apparatus is to secure minute and delicate alterations in the 

 position of the flame-image upon the mirror or prism, since it has been found 

 by the exhibitor that perfectly central illumination can only be secured by 

 having the image of the flame exactly under the optical axis of the sub-stage 

 combination, after the latter has been made to coincide with the optical axis 

 of the object glass. This will enable the microscopist to illuminate the whole 

 field of a :|-inch object glass through an aperture of -j-^th of an inch in 

 diameter. But it can only practically be done by a fine set of mechanical 

 motions in rectangular positions giving perfect command of the position of 

 the flame. 



3597. Apparatus for Continuous Observation of Minute 

 Organisms with the highest powers, by preventing evaporation of 

 the fluid in which the organisms live. 



Rev . W. H. Dallinger and J. J. Drysdale, M.D. 



This apparatus was devised by Messrs. Dallinger and Drysdale for prose- 

 cuting their " Researches into the Life-History of the Monads." It is used 

 upon the ordinary " mechanical stage " of the microscope, so as to admit of 

 the continuous examination under the highest powers of the same drop of a 



