762 SEC. 18. BIOLOGY. 



3529f. Single Microscope, by Tulley and Sons. 



The Royal Microscopical Society. 



3529g. Spectacles, used by the late Robert Brown (4 pair). 



The Royal Microscopical Society. 



3529H. Single Microscope, by Lindsay, 1742. 



The Royal Microscopical Society. 



35291. Large Solar Microscope, complete. 



The Royal Microscopical Society. 



3529J. Single Microscope, in silver, by Culpepper. 



The Royal Microscopical Society. 



3530a. Microscope of Amici. 



Royal Institute of" Studii Superiori" at Florence. 



3531. Microscope, by Campani, in leather case. 



Royal Museum at Cassel (Director , Dr. Finder). 



One of the microscopes by Campani, which Landgrave Charles bought in 

 Rome. 



3531a. The Martin Microscope. 



The Royal Microscopical Society, London. 



Said to have been made by the celebrated Benjamin Martin for Geo. III. It 

 bears no date, but was probably constructed about 1770. For full description 

 see " Williams, On the Martin Microscope," " Transactions of the Microscopical 

 Society," vol. x., 2nd series. It has a triple eye-piece, the middle glass being 

 almost a bull's eye, and insuring a very large field ; .the distance between the 

 two upper glasses and the lower one can be adjusted by a rack and pinion 

 varying in power. The original objectives range from 4 inches to t^h 

 focal length. Higher powers appear to have been added up to J-th ; and there 

 are four high powers up to ^ to be used without the compound body on a 

 small arm which is provided. 



It was supplied with an extensive collection of ancillary apparatus, only part 

 of which is in the possession of the Royal Microscopical Society, by whom it 

 was purchased at a sale of Professor Tuckett's instruments. 



It is remarkable for the variety of its adjustments, general beauty of work- 

 manship, and for special contrivances for various objects of unusually large 

 dimensions. There are, however, obvious faults of construction, interfering 

 both with convenience and steadiness. Its highest optical powers do not 

 produce a good definition of such an object as the scales of Morsch's machine 

 easily displayed by very much lower modern achromatics. 



3531b. American Reflecting Engiscope. 



The Royal Microscopical Society, King's College, London. 

 This is fully described by Dr. Goring in " Micrographia," 1837. The 

 principle is due to Amici ; this particular form to Dr. Goring and Mr. Cuth- 

 bert, by whom it was made. The body of the instrument acts as an eye- 

 piece. The narrow tube resembles a Gregorian reflector. A small inclined 

 mirror receives the image of the object and transmits it to a larger one, which 

 forms a magnified image viewed by the eye-piece. The various arrangements 



