Maech 25, 1898,] 



SCIENCE. 



417 



cultivate a single food plant anywhere over 

 their vast area; but it is nearly paralleled by 

 North America (north of Central America), 

 where not a single indigenous plant was 

 cultivated except perhaps the sunflower 

 (maize was from Central America). Cen- 

 tral and South America could show maize, 

 manioc, tomatoes, potatoes, beans, cacao, 

 tobacco, yams, etc. Africa was the home 

 •of the d urra and probably of coffee, though 

 the latter seems to have been cultivated 

 first in Arabia. Cereals were the staples 

 of western Europe and Asia from the earli- 

 est times, as rice was of eastern Asia. The 

 influence which the culture of these articles 

 •of food exercised on the daily life and 

 "thoughts of earlj' tribes was profound, as is 

 witnessed by their mythology and laws. 

 D. G. Brinton. 

 University of Pennsylvania. 



ASTEOPHYSICAL NOTES. 



In Circular No. 19 of the Harvard Col- 

 lege Observatory Professor E. C. Pickering 

 -announces the results of the examination 

 of the spectra of stars in the large Magel- 

 lanic cloud on plates taken with the Bruce 

 photographic telescope at the Arequipa 

 station. Six stars in this region, in Right 

 Ascension about 5h. 30m. and South 

 Declination about 69°, are found to have 

 spectra of the fifth type (' Wolf-Rayet ' 

 type; Vogel's IK), consisting largely of 

 bright lines. The position of these stars is 

 unusual, as they lie over thirty degrees 

 from the Milky Way, while all the stars of 

 1ihis class previously discovered, sixty-seven 

 in number, have the remarkable peculiarity 

 •of being situated very near the central line 

 •of the Milky Way, their galactic latitude 

 •on the average being less than 3°. 



In the same region seven stars were 

 found whose spectra are of the first type, 

 but with bright hydrogen lines. The 

 number of known stars with this variety of 

 spectrum has been greatly increased in the 



past few years in the progress of the Henry 

 Draper memorial. 



Circular No. 21 states that the bright 

 hydrogen line H/S, discovered in the spec- 

 trum of the southern star No. 9181 of the 

 Argentine General Catalogue in 1895, ap- 

 pears to be variable in that star. It was 

 bright in October, 1897, but invisible on De- 

 cember 27th. Announcement is also made 

 that Mrs. Fleming finds, on examination of 

 Draper memorial plates, that /J Lupi is a 

 spectroscopic binary, with a period not yet 

 determined. The approximate relative 

 velocities of the recently discovered spec- 

 troscopic binaries //' Scorpii and 4- G. C, 

 No. 10,534, are given as 460 and 610 kilo- 

 meters per second, respectively. 



Circulars Nos. 22, 23, 24. and 23 refer 

 chiefly to matters of visual and photo- 

 graphic photometrj'. From a comparison 

 of the constancy of the comparison stars 

 used in determining the variations of over 

 sixty variables found by Professor Bailey in 

 the cluster Messier 5, it appears that any 

 errors due to irregularity in the sensitive- 

 ness of the film on a plate are too small to 

 be detected with certainty. The average 

 deviation of five comparison stars on 35 

 plates, involving over four thousand esti- 

 mates of brightness, was but 0.02 magni- 

 tude, which includes the errors of observa- 

 tion and those from neglecting hundredths 

 of a magnitude in the individual estimates. 



By the addition of a second double- image 

 prism to the polarizing photometer long in 

 use at Harvard, so as to produce coinci- 

 dence of the emergent pencils from the two 

 stars compared, the previously high ac- 

 curacy of the observations has been in- 

 creased. Eight measures, by Mr. 0. C. 

 Wendell, of the difference in brightness of 

 two stars on a recent evening gave the sin- 

 gular and unusual degree of accordance of 

 all the measui-es within 0.01 magnitude. 



From a series of measures, by Wendell, of 

 the brightness of the short period variable, 



