SCIENCE. 



141 



the marsupials. Dr. A. F. A. King read a paper on Sep- 

 tennial Periodicity, drawing attention to the phenomena 

 of menstruation, cestration in animals, gestation, con- 

 tagions, epidemics and climax of fevers. He was par- 

 tially supported by Mr. Goocle, who said that since the 

 lunar month of four weeks had such an important bear- 

 ing upon tides, etc., there is no absurdity in supposing 

 that the same cause may have been at work through 

 myriads of years to bring about periodicity as indicated 

 in the paper. Professor Riley, Mr. Ward, the President, 

 Dr. Prentiss, and others, took the opposite side of the 

 question. 



The Anthropological Society. — Major J. W« 

 Powell, the President, being in the Chair, the following 

 papers were read : " Politico-Social Functions," Lester 

 F. Ward ; "The Savage Mind in the presence of Civiliza- 

 tion," by Otis T. Mason. Mr. Ward first drew attention 

 to the schism which ever manifests itself between theory 

 and practice. Political philosophy taught in the schools 

 is one thing, political rules and maxims of society are quite 

 another. The speaker criticised the interpretation ot the 

 old legal school of politics as well as the modern natural- 

 istic school. The latter, in holding that nature's fixed 

 laws cannot be violated, forgot to include in nature the 

 struggles of human reason. This is well exemplified in 

 the anecdote concerning Plato. When about to flog a 

 slave for stealing, the latter thought to get off by crying, 

 " It is my fate to steal." The philosopher quickly re- 

 minded the slave that it was also his fate to get thrashed 

 for his theft. The paper took the ground that Society 

 was tending more and more to protection, and, from a 

 large collection of statistics showed that gradually new 

 interests were passing under control of the State. Major 

 Powell warmly endorsed Mr. Ward's remarks, and affirmed 

 that the conviction had been growing upon him in favor 

 of the following view : Society begins with the kinship 

 tie, passes on to the property basis of organization, and 

 culminates in the evolution and protection of industries. 

 Mr. Mason's paper was partly theoretical and partly prac- 

 tical. Under the first head it was maintained that the 

 conflicts of the human family in all time had brought the 

 different races of men face to face with higher and better 

 methods, and from these much aid had been received in 

 their own advancement. The practical portion of the 

 paper related to the education of our Indians. The 

 speaker had gone over the history of the subject, had cor- 

 responded with every respectable school and college in 

 the country, and had collected the statistics of govern- 

 ment operations from the Indian Bureau. The conclu- 

 sion arrived at was that much had been wasted through 

 ignorance of anthropological methods, and that the 

 organization of a Bureau of Ethnology had been the 

 wisest scheme the government had undertaken in this 

 regard. 



MICROSCOPY. 



We have received from Dr. William Hailes, of the 

 Pathological Laboratory, Albany Medical College, speci- 

 mens of . injected preparations cut with his improved 

 microtome, which was figured and described on page 

 187, vol. 1, of "Scieistce." The sections are from the 

 kidney of the cat, and are very perfect, showing the ex- 

 cellence of his microtome and his own methods of 

 manipulation. Dr. Hailes also sends us three photo- 

 graphs of magnified specimens of theEmbiyo of the 

 Chick, taken, respectively 24, 36, and 72 hours after 

 commencement of incubation. These photographs are 

 highly interesting, and may be seen at our office by those 

 pursuing such studies. 



Messrs. Lennis and Duncker, both of Berlin, have pub- 

 lished an interesting paper in the Zeitschrift fur Mikros- 

 kopische Fleischschau on a new parasite with which 

 they have met while performing their official duty. In 



examining pork for trichinae they discovered a vermicular 

 diatomea imbedded between the muscular fibres which 

 they describe in the following terms : It is exceedingly 

 thin and transparent, of a greyish color, and of about 

 the size of the cyst-wall of a trichina. 



Professor Leuckardt is inclined to consider its pres- 

 ence in the pork as accidental, and believes that it is of 

 little importance to government inspectors of meat in 

 their official work. 



A writer in Nature makes the following observa- 

 tions on the minute structure of metals hammered into 

 thin leaves which are quite instructive. Notwithstanding 

 the great opacity of metals it is quite possible to procure, 

 by chemical means, metahic leaves sufficiently thin to 

 examine beneath the microscope by transmitted light. 

 Such an examination will show two principal types of 

 structure, one essentially granular and the other fibtous. 

 The granular metals, of which tin may be taken as an 

 example, present the appearance of exceedingly minute 

 grains, each one being perfectly isolated from its neigh- 

 bors by still smaller interspaces. The cohesion of such 

 leaves is very small. 



The fibrous metals, on the other hand, such as silver 

 and gold, have a very marked structure. Silver, especi- 

 ally, has the appearance of a mass of fine, elongated 

 fibres, which are matted and interlaced in a manner 

 which very much resembles hair. In gold this fibrous 

 structure, although present, is far less marked. The in- 

 fluence of extreme pressure upon gold or silver seems to 

 be, therefore, to develop a definite internal structure. 

 Gold and silver, in fact appear to behave in some re- 

 spects like plastic bodies. When forced to spread out 

 in the direction of least resistance their molecules do not 

 move uniformly, but neighboring molecules, having dif- 

 ferent velocities, glide over one another, causing a pro- 

 nounced arrangement of particles in straight lines. 



A new edition of Messrs. Beck's catalogue corrected 

 to the first of this month has been received. It is a 

 work of 176 pages, well illustrated and appears to cover 

 all the wants of a microscopist. Mr. W. H. Walmsley, 

 the manager of the American branch of this house, in- 

 forms us that there is a large demand for microscopes at 

 this time, and that orders are in advance of their means 

 of producing instruments. We notice some change in 

 the prices and that the " Economic " has been raised to 

 $40 including objectives. Messrs. Beck & Co. have 

 been very successful in producing good models for their 

 microscopes, and their workmanship is excellent. Both 

 Mr. Beck and Mr. Walmsley are accomplished micro- 

 scopists, and can thus anticipate the requirements of their 

 customers. 



ASTRONOMY. 



VARIABLE STARS OF SHORT PERIOD.* 



Under the above title, Professor Pickering has read 

 before the American Academy of Arts and Sciences, the 

 second of two papers, both of which are to be regarded 

 as preliminary, rather than final discussions, upon the 

 causes of variability in the light of fixed stars. In the 

 preceding paper (Proc. Amer. Acad. XVL, 1.) the fol- 

 lowing classification of variables was made: 



I. Temporary stars. Examples, Tycho Brahe's star 

 of 1572, new star in Corona 1866. 



II. Stars undergoing slight changes according to laws 

 as yet unknown. Examples o Ceti and x Cygni. 



III. Stars whose light is continually varying, but the 

 changes are repeated with great regularity in a period 

 not exceeding a few days. Examples, /3 Lyrae and 

 '5 Cephei. 



IV. Stars which every few days undergo for a few 

 hours a remarkable diminution in light, this phenomenon 



* Proceedings of the American Academy of Arts and Sciences, Vol. 



