April 2 J, 1887] 



NA TURE 



595 



An experimental passenger-train, lighted throughout by elec- 

 tricity, and heated by steam from the engine, is now running 

 between New York and Boston. Each car 15 illuminated by 

 eighteen i6-candle glow-lamps, the current being derived from 

 storage-batteries beneath the floor-timbers, charged for ten hours 

 by dynamos. Both light and heat are said to be ample, and 

 Scit-ncc believes that danger from fire, in case of accident to the 

 train, is much lessened, if not almost wholly done away with. 



M.\C11IXERY for winding silk from cocoons was lately set up 

 at ^Yashington by the Department of Agriculture. Much interest 

 is manifested in the experiments, and the demand for copies of 

 the Bulletin on Silkworm Culture is so gre it that it has been 

 necessaiy to issue seven or eight editions, .\ccording to officials 

 of the Department of Agriculture, the .'equests for silkworm 

 eggs have never been so numerous since the Department began 

 their distribution. It is expected, therefore, that large quantities 

 of American-grown silk will be placed upon the market this 

 year. 



When crossing the Atlantic, Prof. Dennis, of New York, 

 recently mad; .=ome observations to test the purity of the ocean- 

 air. He had previously prepared capsules of sterilised gela- 

 tine. One which was exposed in a state-room on the main 

 deck of the steamer developed five hundred points of infection 

 in eighteen hours ; one exposed in the cabin on the main 

 deck developed only five or six points in ten days ; a third, 

 hung over the bow of the ship for ten days, remained uncon- 

 ta;ninated. 



Mk. V. G. E.\TOX, writing to the Popular Scu-iice Monthly, 

 says th.it in most of the eastern cities of the Unites States 

 fully 30 per cent, of the men over thirty years of age show 

 unmistakable signs of baldness, while nearly 20 per cent, have 

 spots on their hea is that are n t only bald, but poli-shed with 

 the gloss that is supposed to belong to extreme old age alone. 

 He has beec in most of the chu ches and theal res in all the large 

 eastern cities, as well as in Chicago, St. Louis, and other places 

 of the West, and has verified his assertion by actual count. He 

 has found that bald-headed men are most plentiful in New York 

 and Boston, and that after these cities come Philadelphia, 

 Washington, and the western towns. The following are a few 

 of his observations taken in Boston : — Trinity Church : 243 

 men ; 71 actually bald, 46 indications of baldness. King's 

 Chapel : 86 men ; 38 actually bald, 14 indications of baldness. 

 Hollis Street Theatre, orchestra at performance of the 

 " Mikido " : 63 men ; 27 actually bald, ro i.idications. Bos- 

 ton Theatre, Judic : 126 men ; 51 actually bald, 43 indications. 



Thi-: additions to the Zoological Society's Gardens during tlie 

 past week include two Polar Bears (Ursus mariliiiius), from the 

 Polar Regions, presented by Mr. Joseph Monteith ; two Brown- 

 throated Conures (Coniinis trrughioms), from South America, 

 presented by Lieut. General Newton; a Ring T)ove {CWumda 

 palunib.triiis), a Turtle T)o\e {Tiir/iir communis), British, pre- 

 sented by Mr. C. L. Sutherland, F.Z.S. ; a Secretary Vulture 

 (Sn-frntni-iiis rcpiilivorus), from South Africa, presented by Mr. 

 J. Newbury ; a White-tailed Buzzard [Bvtco albicauJahis), from 

 America, presented by Mr. John Lloyd ; two Common Gulls 

 (Larus caiiiis), British, presented by Mr. J. A. Cotton; two 



Ducks ( ) from the Falkland Isles.presented by Mr. F. 



E. Cobb, C.M.Z.S. ; two Viscachas (Lagostomus trichodactylm), 

 born in the Gardens. 



OUR ASTROXOMICAL COLUMN 



The U.S. Naval Observatory.— We learn from Science, 

 vol. ix. No. 217, that the new Naval Observatory, for which 

 Congress appropriated 400,000 dollars several years ago, is to 

 be tjuilt forthwith. Mr. R. M. Hunt, of New York, has been 

 appointed architect of the building, and opera'.ions will shortly 

 begin. 



Researches on the Sl'.n's Diameter. — Prof. Di Legge, 

 of the Campidoglio Observatory, Rome, has published in 

 Atti della R. Accademia dci Lined, ser. 4, vol. i., a discussion 

 of the meridian transit observations of the sun's diameter taken 

 at the Observatory during the years 1874-S3. From May 1876 

 the observations were made by projecting the sun's image on a 

 screen, so that tsvo or more persons could observe simultaneously, 

 and thus determine their "personal equations" from observa- 

 tions made under precisely similar circumstances. Altogether, 

 5796 transits were observed on 2213 days, giving an average of 

 221 days per annum. The mean resulting horizontal semi- 

 diameters of the sun, collected in biennial groups, show a pro- 

 gressive diminution, which, taking into consideration Aiiwers' 

 researches on the subject (Nature, vol. xxxv. p. 496), are most 

 probably due to change in the habits of the observers, as the 

 table of mean annual personal equations given by Prof Di 

 Legge would also lead us to infer. The mean values of the 

 horizontal semi-diameter at mean distance found from each 

 observer's transits are respectively as follows ; — Di Legge, 

 96i"-329 ± o"'oii ; Respighi, 96o"76o ± o"'oi3 ; Giacomelli, 

 96i"'307 ifc o"'Oi2; and Prosperi, 96i"'356 ± o"'oi4; the 

 combined mean value being 9t5l"'i88. 



ASTRONOMICAL PHENOMENA FOR THE 



WEEK 1887 APRIL 24-30 



/ppOR the reckoning of time the civil day, commencing at 



^ ■'• Greenwich mean midnight, counting the hours on to 24, 



is here employed. ) 



At Greenwich on April 24 



Sun rises, 4h. 48m. ; souths, llh. 5Sm. 5 '65. ; sets, I9h. 8m. ; 



decl. on meridian, 12° 51' N. : Sidereal Time at Sunset, 



9'.i. 18m. 



Moon (at First Quarter on April 30) rises, 5h. 48m. ; souths, 



I2h. 55m. ; sets, 20h. 14m. ; decl. on meridian, 12° 11' N. 



OccuUations of Stars by the Moon (visible at Greenwich) 



Corresponding 

 'esfron 



Mag. Disap. 



21 36 



I 4 



22 27 



tex to right for 

 inverted image 



■•■ 85" 359 

 ... 119 293 

 ••• 74 330 



Mars in conjunction with the Sun. 



Venus in conjunction with and 6° 19' north 



of the Moon. 

 Saturn in conjunction with and 3° 6' north 

 of the Moon. 



