40 THE AMERICAN MONTHLY [Mar. 



you possess. A handsome slide under an inch objective 

 will excite more than a triumph of manipulation under a 

 one-tenth. The beak of a mosquito will produce a total 

 eclipse of Bacillus tuberculosis. It is unwise to use 

 high objectives at such a soiree. 



SCLEROGEN. — This tissue is finely exhibited in the grit 

 of a pear. With a penknife, cut as thin a section of a 

 ripe pear as possible. Place the section on a glass slip, 

 under a thick cover. Press out the section and examine. 

 To press out, wrap the finger with a clean handerchief . 

 The naked finger would grease and soil the cover. The 

 specimen is easily prepared and is well worth examin- 

 ing. _^ 



EDITORIAL. 



Image of an Image.— Dr. T. O. Reynolds writes that 14 

 years ag-o he experimented in the line that Gates has suc- 

 ceeded in. He had a B. and L. Investigfator and another 

 inferior instrument with which he tried to g-et an image of 

 an image. He was discouraged because he did not get the 

 focusing of the second instrument accurately determined. 

 He overlooked the fact that the attenuation of light, due to 

 the extreme magnification, rendered the image, which was 

 really there, invisible to the human retina. He has always 

 believed that it would be accomplished, and that the mole- 

 cule and atom would be revealed as plainly as the mark- 

 ings of -Pleurosigma. He was therefore in the opposite 

 mood from those silly egotists who have ridiculed the 

 matter in the petty prints of the day, and hails with entire 

 credence the announcement that Gates has by long ex- 

 posure of a sensitive photographic plate got the cumula- 

 tive action of light which the eye could not gather. He 

 looks for an unlimited expansion of our powers in this 

 way. 



Fish Commission. — Natural Science, oi London, announces 

 a long list of appointments to professorships and govern- 



