200 



SCIENCE. 



[Vol. Yl., No. 136. 



cholera. Four gentlemen, Dr. John B. Hamilton, 

 Dr. H. Rausch, Dr. C. Peters, and Dr. H. C. Wood, 

 have each tried to answer the question : Can cholera 

 be averted? In these papers the germ origin of 

 cholera is admitted, but no particular bacillus is fixed 

 on as the cause of the disease. The best methods of 

 disinfection, etc., are spoken of, isolation of the sick 

 recommended, and the necessity of cleanliness is 

 urged; but no facts or theories are set forward of 

 which the public are not already in possession. 



Besides the notes on dogs and cholera, there have 

 also appeared one or two other articles which might 

 be called semi-scientific. In the Gentlemen'' s maga- 

 zine, there is an interesting and well written paper 

 on the wild cattle of North America, by C. F. Gordon 

 Cummings, describing the appearance, distribution, 

 and extinction of the American bison ; and the Co7'n- 

 hill magazine has a very popular article on the ' Birth 

 of mountains.' 



— The Alabama state signal-service found it im- 

 practicable to use the same signals employed by the 

 Ohio service, for three reasons : 1°. Because the rail- 

 road refused to allow red to be used on their lines. 

 2°. On account of the considerable cost of the Ohio 

 set of signals (eighteen to twenty-four dollars); and 

 3°. From the fact, that, in a calm, it was found impos- 

 sible to distinguish between the star, the crescent, 

 and the sun. After correspondence with the U. S. 

 chief signal-ofiicer, five flags were determined on ac- 

 cording to the accompanying illustrations. Their 



WHITE. 



Fair or clear 

 weather. 



BLUE. 



Qeoeral rams. 



ORANGE. 



Looal raiuf. 



Tempera- 

 ture 

 tiynah 



CoJd-wave 

 signal. 



cost when made of bunting is something less than 

 that of the Ohio flags: and when made of cotton 

 cloth, the outlay is only a few cents each; while the 

 solid colors allow the predictions to be read at a con- 

 siderable distance. The railroad authorities have 

 entered cordially into the system, and telegraph the 

 predictions free of charge; except in the case of two 

 or three companies not owning their telegraph lines, 

 who expose the signals on their trains. In most cases 

 they are hung on poles. The black triangular flag 

 when placed above indicates rising temperature; 

 when placed below indicates falling temperature; if 

 absent, indicates stationary temperature. 



— On account of the lack of funds necessary to 

 maintain its activity, the astronomical observatory of 

 Beloit college, Wisconsin (Prof. J. Tatlock, jun., di- 

 rector), has been closed. 



— The annual meeting of the American forestry 

 congress will be held at Boston, beginning Sept. 22, 

 under the auspices of the local societies of horticul- 

 ture and agriculture. Mr. W. C. Strong of the Hor- 

 ticultural society is chairman of the local committee, 

 and Mr. Daniel Needham of Boston is the chairman 

 of the sub-committee of accommodation; and to the 

 latter, requests for special arrangements for board 

 should be sent. The hotel headquarters will be at 



the Adams House. Three sessions daily will be held 

 at Horticultural Hall. Monday, Sept. 22, will be 

 given up to addresses, reports, and general business; 

 Wednesday, to the reading of papers and discussions; 

 and Thursday, to excursions, — among others, to the 

 Arnold Arboretum. Over twenty papers have already 

 been promised, and many others are expected. The 

 discussions will be conducted as far as possible under 

 the following heads: 1°. Importance of forests in 

 climatic and hydraulic respects, and in regard to 

 other industries. 2°. Duties and rights of the state 

 to protect her forest resources. 3°. Forest fires : causes ; 

 laws and methods for their restriction. 5°. Education 

 and research in forestry matters : arbor days ; schools; 

 lectures; exhibits; experiment stations; press; asso- 

 ciations. 5°. Practical forestry : prospects, methods, 

 profits, etc. 



— If any indication of the mathematical activity of 

 different nations is afforded by the number of those 

 who have published contributions bearing upon one 

 of the most notable of recently developed branches 

 of mathematical investigation, England is at this 

 moment occupying a very subordinate position in the 

 advancement of pure mathematics. A bibliography 

 of the modern theory of linear differential equations, 

 which appeared in the last number of the American 

 journal of mathematics (vol. vii.. No. 4), gives in all 

 sixty-eight writers, of whom only two are English, 

 while twenty-seven are French, seventeen German, 

 nine Italian, and the rest are divided among eight 

 different nationalities, there being one American. 

 This disproportion between the English and the 

 French or Germans, is greatly increased, when the 

 number and importance of the memoirs contributed 

 by the various writers are taken into account. 



— We learn from U astronomic that the crown disk 

 for the great thirty-six-inch refractor of the Lick ob- 

 servatory, referred to in an earlier column, has recently 

 been delivered to Alvan Clark & Sons, by Feil, the 

 celebrated Paris jnanufacturer of optical glass. The 

 elder Feil has reorganized the establishment, associat- 

 ing with himself his son and M. Mantois. The two 

 disks for the thirty-inch Nice refractor have been 

 placed in the hands of the Henry brothers, who take 

 charge of the optical work ; and it is hoped that the 

 glass will be finished in October. 



— The American philological association will hold 

 its next meeting at Cornell University, Ithaca, N.Y., 

 on July 13, 1886. The presiding officer will be Pro- 

 fessor Tracy Peck of Yale college. 



— i\raiMre states that it has been decided to with- 

 hold from publication the report of Drs. Klein and 

 Gibbes upon Dr. Koch's discoveries in relation to the 

 germ theory of cholera, until the conclusions of a 

 committee appointed by the secretary of state for 

 India with reference to that report are also ready. 



— Ausland, a German weekly published at Stutt- 

 gart, is now printing an interesting serial upon the 

 influence of the glacial period upon the formation of 

 the physical surface of Lower Germany, by Th. Over- 

 beck, in which Torell's hypothesis is subjected to crit- 

 icism. This weekly is now in its fifty-eighth year. 



