1892.] MICROSCOPICAL JOURNAL. 269 



The secretary announced the receipt of the usual periodicals 

 and journals to which the society subscribes, or which are sent 

 in exchange, and by purchase two very important works, being 

 Doctor Wolle's " Desmids of the United States" and the " Fresh- 

 Water AlgfE of the United States," the latter in two volumes. 

 Acknowledgment was also made of a valuable monograph from 

 the author, Arthur Mead Edwards, M. D., "On Examinations 

 Made by Means of the Microscope of the Specimens of the Geo- 

 logical Survey of California." 



The paper of the evening was read by J. H. Wvthe, M. D., 

 his subject being "The Ultimate Structure of Striated jMuscle." 

 The opinions advanced are the result of years of study and were 

 not made public by the doctor as soon as he had reached the con- 

 clusion. Some of the preparations shown w^ere mounted six 

 vears ago, and all were of a character to demonstrate the claims 

 made by the doctor. 



The paper was listened to with the closest attention, and all 

 expressed themselves pleased and instructed. A vote of thanks 

 was unanimously tendered the speaker for his valuable contribu- 

 tion to a subject of general interest to the scientific world. 



Augtist 3r iSgz. — After the regular routine business the secre- 

 tarv announced the reception of the usual list of periodicals and 

 transactions, together with a pamphlet on " The Examination 

 by means of the Microscope of Specimens from the Geological 

 Survev of California," second edition, from the author, Arthur 

 Mead Edwards, M. D. 



A cluster of carnation plants, on which some disease, fungous 

 or otherwise, was preying, was received from John Pfenninger, 

 of this city. The president requested that members who felt in- 

 terested should take portions for investigation and report at the 

 next meeting. 



The paper of the evening was read by George Otis Mitchell, 

 his subject being "The Principles of Microscopic Vision." At 

 the outsetMr. Mitchell disclaimed any original work on this subject, 

 but stated that he should merely give a resume of the investigations 

 and deductions of Professor Abbe and other eminent students of 

 optics. In dealing with the subject of light, he said, we have 

 left the realm of ponderable matter, with its comparatively slow 

 rates of vibration, resulting in sound and heat, and have to ti^eat 

 of that manifestation of an unknown and unknowable cause, 

 whose velocity is commonly estimated at 186,000 miles, and 

 whose range of vibrations occupies the octave between 400 tril- 

 lions and 800 trillions per second in round numbers. But one 

 subtle form of energy is known to us, that of actinism, or chemi- 

 cal energy, whose laws have not yet revealed themselves. 



A discussion of the various theories which have been pro- 

 pounded to account for the phenomena of light was not attefnpted 

 by the speaker. The one now universally held was framed by 

 Dr. Thomas Young, largely to account for a class of phenomena, 



