126 THE AMERICAN MONTHLY [Apr 



hibited by such an arrangement as Dr. Gates proposes, it 

 is a mooted point whether such appearances would indicate 

 real structure or whether (as is most probable) they would 

 be caused by diffraction spectra. — A. G., Punjab, India, 

 Jan. 22. 



EDITORIAL. 



Stains. — To see more plainly what might otherwise al- 

 most elude 1 detection we vary its setting- or back ground. 

 This is the theory of all micro-staining. If, given a liquid 

 containing tubercle bacillus both of about the same color, 

 we can stain the liquid or the germ, we produce a visible 

 contrast. Ingenuity has now enabled us to invent stains 

 which will affect germ and containing fluid differently and 

 even produce several different colors in the same infinites- 

 imal speck of matter each color portraying some partic- 

 ular part of the organism. 



Diagnosis. — It will be seen from Dr. Ewing's article 

 that the microscope was of decided practical value in de- 

 termining some of the diseases from which the soldiers 

 suffered at Camp Wikoff after having been subjected to 

 Cuban climate. 



Terms. — An amusing misuse of terms occurred recent- 

 ly. Sir W. Roberts-Austen in an article on steel rails re- 

 ported taking photographs of enlarged images which con- 

 stitutes photomicrography but he entitled his paper Mi- 

 crophotography. A photograph of a large object reduced 

 is a microphotograph. A photograph of a small object 

 which gives an enlarged image is a photomicrograph. Thus 

 all of our illustrations of bacteria etc. being much larger 

 than the objects themselves are photomicrographs. But 

 those curiosities such as the Lord's prayer visible only un- 

 der an objective are microphotographs. The writer has 

 a photograph of the "White House 1 ' brought down so 

 small that it cannot be seen other than as a pin-point speck 

 until placed under a lens. This is a very small or micro- 

 photograph. 



