AND SUPER MICROSCOPE 



from twenty yards to sixty miles may be clearly 

 viewed at one and the same time. 



A few of the unsolved problems confronting the 

 microscopist are reviewed in our concluding 

 chapter. Whether they will ever be solved we dare 

 not venture to say; but, if they are to be, surely 

 to this latest arrival in the microscopic world and 

 to its companion, the super-microscope, the honours 

 will go. 



247 



