l886.] NEW-YORK MICROSCOPICAL SOCIETY. lY 



had tried many forms of batteries for the production of the 

 current, but had found them all unsatisfactory, as the best of them 

 required cleansing, and renewal of chemicals, after running for 

 about three hours. He then attempted the use of a small steam 

 engine fed by illuminating gas, to drive a dynamo. He abandoned 

 this method after ascertaining that no engine of moderate 

 size would give sufificient rapidity to the generator, and that the 

 vibrations imparted to the floors precluded the use of high-power 

 lenses : it was objectionable for other reasons also. He then pro- 

 cured a small gas engine, which was placed in an adjoining room. 

 This gave sufficient rotary velocity to the dynamo to produce a 

 light of between two and three candle-power, and was eminently 

 successful. The engine required no attention, and the noise 

 was barely perceptible. The light is attached to the microscope- 

 stand by a double ball and socket joint, and can thus be placed 

 in any position. It possesses great resolving power, and the ad- 

 vantages of direct illumination over reflected light from the 

 mirror are very pronounced. Mr. Schultze preferred the Swan 

 lamp over all others, there being no projecting point on top, due 

 to closing the bulb after exhaustion. 



Mr. De Witt suggested the advantage of using the electric 

 light in the study of minute organisms with the apparatus em- 

 ployed by Messrs. Drysdale and Dallinger, and described in Kent's 

 Infusoria, plate LI. They were obliged to tilt the microscope 

 to a horizontal position to obtain the required illumination ; this 

 difficulty would be avoided by the use of the Swan lamp. 



An agent of the Gibson Storage Battery Co. exhibited a battery 

 of two storage cells, producing a light of one candle-power, which 

 would run continuously for two and three-quarters hours. The 

 cells might be charged from the arc-light or incandescence lamp 

 currents, or from gravity or other cells. 



POLLEN OF STRELITZIA. 



Referring to the slide exhibited, Dr. N. L. Britton described 

 the pollen as nearly globular and very large. It is mentioned in 

 Edgeworth's "Pollen", p. 17, where its size is given as elf 7 of 

 an inch, which is about 100 //. The grains are filled with 

 granular protoplasm, readily seen with a two-inch objective. 

 Their color is white. 



