58 THE AMERICAN MONTHLY [Feb 



alb., no sugar, urea 4 per cent., uric acid increased. On 

 microscopical examination there is seen in the field a mod- 

 erate number of pale colorless rings (washed out of red 

 blood corpuscles), also a few feebly colored red blood col- 

 puscles. Subsequent examination failed to reveal any 

 such bodies. One month later a second attack, similar to 

 the first. Urine, Sp. gr. 1028, high color, no alb., no su- 

 gar, urea 3 per cent. Microscopical examination revealed 

 a few delicate, ring shaped bodies (washed out red blood 

 corDuscles). One subsequent examination failed to show 

 any such bodies. One day later a patient brought in a 

 small phosphatic stone passed by urethra. 



(2) Urine, Sp. gr. 1028, high color, a trace of albumen, 

 no sugar. Microscopical examination reveals a number 

 of pale, colorless, delicate bordered rings (washed out 

 red blood corpuscles), no casts, a few leucocytes. The 

 woman recovered the following day. An examination of 

 the urine one day later revealed no such bodies. 



(3) Microscopical examination of urine revealed from 

 five to ten red blood corpuscles in the field ; some of them 

 washed out. No casts. A few triple phosphate crystals. 

 Specimen taken two days later showed no such bodies. 



LETTERS TO THE EDITOR. 



GATES' DOUBLE MICROSCOPE. 



Lenal's Apparatus. — Seven years ago, in Zeitschr. f. 

 Wiss. Mikr., Dr. Lenal described his microscope with a 

 second microscope attached to it in place of an eye-piece by 

 means of which he claimed to get greater magnification of 

 the primal image that has been hitherto secured by any 

 combination of eye-pieces and objectives. Dallinger, Nel- 

 son and other English microscopists pointed out that the 

 working power of any objective could not be increased by 

 subjecting the primal image of an approximately perfect ob- 

 ject-glass to examination by a second microscope or other 

 complex combination of lenses. The greater magnifica- 



