2528 Journal of Applied Microscopy 



stand the method of study. Powdered digitalis has been more than once mis- 

 taken for powdered senna. Mixed powders of digitalis and senna can be very 

 readily distinguished by the microscope, and a lantern slide of this mixture 

 would show much more marked difference of structural elements. In the pow- 

 der would appear the simple non-secreting hairs consisting of two to five super- 

 imposed cells, and hairs with two celled glandular head, very characteristic of 

 digitalis powder. 

 School of Pharmacy, University of Kansas. L- E. Sayre. 



Dr. Kasperek has described a very ingenious funnel devised for the purpose 

 of filtering gelatine or agar that needs to be kept warm during filtering. The 

 piece of apparatus consists of an ordinary glass funnel, in which are placed sev- 

 eral layers of asbestos paper, fastened together with water glass, the asbestos 

 paper conforming to the shape of the filter. Between the layers of the asbes- 

 tos there are wound about 3 meters of a 3 millimeter nickel wire, so wound 

 around that the different coils are thoroughly isolated from each other. The 

 two ends of the wire are connected with binding screws. To one of the binding 

 screws is attached an electric wire from an electric current, and to the other 

 a wire that is arranged to pass through a series of ordinary incandescent lights. 

 By connecting the wires with the electric current and turning on a single light, the 

 filter is warmed to a temperature of 42°. By connecting with two lights of sim- 

 ilar power the filter is warmed to (30°, and by the addition of a third light of 

 16 candle-power a temperature of 70° can be obtained. This filter is used in 

 the ordinary way, and is extremely convenient for filtering material that needs to 

 be kept warm. — Journal of State Medicine. 



Quite recently Dr. J. Ruhemann presented to the Berlin Medical Society a 

 new method for the quantitative estimation of uric acid in the urine, which is 

 based upon the principle of the union of uric acid with iodin and is carried out 

 in the following manner : The author had constructed a burette, 25.5 cm. in 

 length, with the following divisions : The lowest mark S shows the height to 

 which the indicator, sulphid of carbon, should reach. Then follows to the mark / 

 a space of 2 c. c. content in which iodin solution is filled. The latter solution 

 is composed of iodin, 1.5 ; potassium iodid, 1.5 ; alcohol, 15.0 ; and water, 185.0. 

 Above the mark /, at 2.0, begins an empirical scale which, at distances of 0.2 

 c. c, gives the uric acid value pro mille. It runs from 2.45 to 1.175 gm. pro 

 mille. After the sulphid of carbon and iodin solution have been placed in the 

 burette, observing the precautions laid down by Ruhemann, the urine is slowly 

 added and the mixture vigorously shaken after each addition. The urine is 

 added until the primary brown color gives place to a white color, at which 

 moment the percentage of uric acid is read off by the aid of the figures at the 

 top of the column of fluid. The procedure requires, on an average, about 30 to 

 45 minutes. Ruhemann claims for his method rapidity and an accuracy equal 

 to that obtained by the weight analysis method. — The Post Graduate. 



