218 MEASURING BRINELL IMPRESSIONS 



The support A consists of the foot, a mount, a split collar provided 

 with a clamping screw and a handle. The microscope fits with 

 gentle friction into the collar, so as to be definitely adjustable with 

 respect to the impression to be measured; it is then fixed in that 

 position by means of a screw C. In the base of the support is 

 encased a disc of fibre B, which is provided with a central aperture 

 through which the impression to be measured can be examined. 

 This fibre washer, as shown in the annexed diagram and in the model, 

 may be replaced by a washer of suitable shape, so as to be adaptable 

 to the piece to be examined by the microscope. The microscope 

 weighs 0.390 kg.; the mahogany case weighs 0.650 kg. 



