OF METALLURGICAL MICROSCOPES 139 



(h) Eye-pieces. — These give the least trouble of all the parts of 

 the microscope, the quality being usually satisfactory. 

 Projection eye-pieces are to be preferred for photographic 

 work. 



These few notes are presented by way of suggestions for dis- 

 cussion. Each worker will have formed some opinion on the points 

 mentioned, and a comparison of such opinions may be of assistance 

 to manufacturers in determining the design of their future instru- 

 ments. There is a large demand for metallographic microscopes at 

 present, whilst the supply is very limited, and the time seems appro- 

 priate for a consideration of the question whether improvements 

 might not be made in the light of experience. 



