August 19, 1910] 



SCIENCE 



247 



paper on the " Damping of the Oscillations 

 of Swinging Bodies by the Resistance of the 

 Air " which I published last year, must have 

 been somewhat affected by a minute spark 

 which escaped my notice, but which lasted 

 for perhaps the thousandth part of a second 

 and thus effectually prevented the break in 

 the circuit of the deflecting current from 

 being abrupt? The very interesting discon- 

 tinuities in the motion of bodies swinging 

 under certain laws of damping are not very 

 appreciable in the air at the small velocities 

 described in the paper mentioned. 



Harvard University B. O. Peirce 



SCIENTIFIC BOOKS 

 Birds of New York. By Elon Howard 

 Eaton. Memoir 12, New York State Mu- 

 seum, John M. Clarke, Director. Part I. 

 Introductory Chapters; Water Birds and 

 Game Birds. Albany, University of the 

 State of New York. 1910. 4to, pp. 501 

 (-\- 160 pp. of unpaged tabular matter be- 

 tween pp. 86 and 87), 42 colored plates, and 

 many half-tone illustrations in the text. 

 Of the many manuals and reports on birds 

 issued under the authority of the various 

 state governments none approaches in volumi- 

 nous detail and fullness of illustration the 

 present work (which will form two thick 

 volumes in quarto) on the " Birds of New 

 York," of which Part I., comprising the in- 

 troductory matter and the water birds and 

 game birds, has recently appeared. The au- 

 thor, Elon Howard Eaton, has shown himseK 

 well fitted for the task, both the introductory 

 matter and the systematic part giving evi- 

 dence of thorough research and good judg- 

 ment. The present work is therefore a worthy 

 successor to the illustrated quarto volume on 

 birds by Dr. J. E. DeKay, published in 1844 

 as Part II. of the " Natural History of New 

 York " — a work of great usefulness for many 

 years, beyond as well as within the boundaries 

 of the state. 



The first part of the present work opens 

 with a " Summary of the New York State 

 Avifauna," in which the 411 species that have 

 been recorded as occurring in the state are 



classified in six categories, in accordance with 

 their manner of occurrence, as residents, sum- 

 mer residents, transients, winter visitants, 

 summer visitants and accidental visitants. 

 This is followed by a consideration of the life 

 zones of the state, namely, the Canadian, Alle- 

 ghanian and Carolinian, illustrated by a map 

 shaded to indicate relative elevation, with 

 cross-hatching in red and blue to demark the 

 life zones; but unfortunately many of the 

 place names are practically illegible, even 

 with the aid of a hand-glass. Other smaller 

 maps of similar character illustrate the breed- 

 ing ranges of twenty-two species, while sev- 

 eral pages of charts graphically indicate the 

 breeding ranges of all the species that breed 

 in the state with reference to their represen- 

 tation in the different life zones. Considera- 

 tion of the Mount Marcy region, of the in- 

 crease and decrease of species and the cause, 

 a few pages of appropriate " suggestions to 

 bird students," and such other topics as 

 " bird migration," " spring arrivals," " county 

 schedules " and " classification," make up the 

 rest of the 90 pages of introduction. Under 

 " spring arrivals " the dates of arrival of 90 

 species at 30 localities are given for a series 

 of years in three tabular inserts, and two 

 maps show the dates of spring arrival of tie 

 Baltimore oriole and barn swallow for the 

 year 1905 at different points throughout the 

 state. Under " county schedules " an attempt 

 is made " to show in condensed form the 

 status of our knowledge concerning the birds 

 of each county in New York State." This 

 laborious compilation is tabulated in 75 in- 

 serts placed between pages 86 and 87. 



The systematic part (pp. 91-390) follows 

 the classification and nomenclature of the 

 American Ornithologists' Union Check-List 

 of North American Birds, and includes the 

 species from the grebes to the end of the pig- 

 eons. Diagnoses are given of the family and 

 higher groups, with some additional comment, 

 as well as of the species. The matter re- 

 lating to the latter is classified under the sub- 

 headings " description," " field marks," " dis- 

 tribution," " migration," " haunts and habits," 

 " food," " nests and eggs," etc., and varies in 



