November 3, 19 10] 



NATURE 



21 



in decrease of the temperature gradient per lOO metres 

 lie lower 2 kilometres were obtained (i) above the land 

 1 a captive balloon and light wind; (2) above the 

 i with a moderate westerly wind, with kites; and (3) 

 ve the sea (January 14-20), weather rainy, with kites; 

 the results are not strictly comparable, owing to 

 rences of time of day : — 



Metres IOO-5CO 500-icco 1000-1500 



Balloon ... o 77- C. ... 0-37- ... — 

 Kite(lan«^)... 087 •■ 072 ... 044 (<I500M) 



Kite (sea)... O 91 ... 059 ... 0-]l 



Further kite observations over sea gave for 1500-2000 m., 

 0-34°; 2000-2500 m., 050°; 2500-3000 m., 0-46°. At 

 about 1000 m. the gradient shows a sudden decrease, prob- 

 ably due to the formation of cumulus clouds. The observa- 

 tions of wind direction for the period September-May show 

 that the upper air-current has easterly components up to 

 the greatest heights attained (10-15 km.). The average 

 altitude of the west monsoon was 5-4 km. The upper 

 easterly, as well as the lower westerly, winds were some- 

 times affected by strong northerly or southerly components. 

 It is mentioned that diagrams of a registering balloon sent 

 up on May 19, during the passage of the earth through 

 tfie tail of Halley's comet, showed no other noteworthy 

 feature than an inversion of temperature between 6 and 

 7 km. ; the balloon burst at about 7 km. 



The various methods of finding the height of an airship 



are discussed by Captain Paul Renard in the Revue 



scientifique for September 17. Of the several methods of 



observing the height from the airship itself. Captain 



Renard considers that the use of the barometer affords 



only practicable one. Of the methods of observing 



height from the ground the large majority involve 



- niultaneous measurement of several angles, and this is, 



general, impracticable. Captain Renard considers that 



best methods are by observation with a telemeter, 



.;pled with a determination of the altitude, or by two 



•ultaneous observations of the altitude at the instant 



airship is in the vertical plane joining the two 



-•?rvers. , 



The Builder for October 29 contains an illustrated article 

 'i-scriptive of the fine building now being erected in London 

 : the Y.M.C.A. This building occupies an island site of 

 ne 33.000 square feet, bounded by Great Russell Street, 

 dford .Avenue, Tottenham Court Road, and Caroline 

 r-»et. Reinforced concrete plays an important part, and 

 ^ been employed for the solution of various structural 

 roblems of considerable magnitude. The building is not 

 •:- of the reinforced concrete skeleton class merely 

 athed in masonry-, but rather is a combination of 

 isonry with reinforced concrete, the latter material 

 king the duties hitherto very generally assigned to 

 uctura' steel-work in modern architecture. Thus we 

 d reinforced concrete columns, beams, and wall lintels 

 rming the backbone of masonry features, and bearing a 

 rge proportion of the loads to be supported, yet without 

 \olving any noticeable departure from the familiar aspect 

 masonry. In some important respects reinforced con- 

 .-te is exclusively adopted, as in floor, roof, gallery stair- 

 vay, and swimming-bath construction, and in the form 

 of exceptionally large girders. The details of the rein- 

 forced concrete work were prepared by Messrs. L. G. 

 Mouchel and Partners, in accordance with the Hennebique 

 system. 



-An article by Mr. Fullerton L. Waldo on recent pro- 

 gress in the construction of the Panama Canal appears in 

 the Engineering Magazine for October. Rapid progress 



NO. 2140, VOL. 85] 



has been made in the great lock-works and the huge dam 

 that is rising at Gatun. The three lock flights divide the 

 vertical distance to the 85-foot level between them, whereas 

 the locks of the Pacific division have lifts of 33 1 feet and 

 54§ feet respectively. The usable dimensions of the locks, 

 are 1000 feet by no feet, giving ample margin for even 

 the new White Star liners, the overall dimensions of which 

 are 890 feet in length and 92 feet in width. It is calcu- 

 lated that the lock-stair at Gatun will require about 

 I J hours for the transit ; the Pacific locks will detain the 

 vessels for about the same length of time. The total 

 passage across the Isthmus wilj take about 10 to 12 hours. 

 The train takes about 2 J hours, so that passengers will 

 probably prefer this method of transit. About 15 minutes 

 are required to fill the lock chamber, but in case of need 

 for haste the process can be completed in about half this 

 time. The available water supply will allow of 48 ktckages 

 per day, which might mean an average of something like 

 80,000,000 tons of traffic annually as compared with- 

 21,000,000 tons in the case of the Suez Canal and the 

 40,000,000 tons of the Sault Ste. Marie. 



We have received the first five numbers of a leaflet 

 entitled Hygieia, which is published by the Bureau of the 

 International Congress of Hygiene, which is to be held in 

 Dresden in 191 1. It contains notices with regard to the 

 congress and brief abstracts of papers dealing with sub- 

 jects appertaining to hygiene, e.g. sugar as a food-stuff, 

 taverns as hospitals, cleansing of towns, &c. 



Messrs. Newton .\sd Co., Fleet Street, London, have 

 issued a supplementary list of lantern-slides for the present 

 session. .Among many others, we notice numerous astro- 

 nomical slides dealing with Halley's comet, the moon, and 

 Greenwich Observatory ; a set of slides showing Sicily and 

 Messina after the earthquake ; sets to illustrate eight lec- 

 tures on India, drawn up by Mr. H. J. Mackinder for the 

 Visual Instruction Committee ; and slides showing aerial 

 experiments and aeroplanes. 



The Penny Science Lectures at the Royal Victoria Hall. 

 Waterloo Road, S.E., during November include : — 

 November 8, " Early Men in Britain," W. Lower Carter,, 

 and November 22, " Liquid Air," Dr. R. Whittan Gray. 



Mr. H. K. Lewis, of Gower Street, London, has pub- 

 lished a catalogue of new books and new editions added 

 to his well-known medical and scientific circulating library 

 during July, August, and September of this year. 



OUR ASTROXOMICAL COLUMN. 



FiREB.\i.L OF October 23. — Mr. W. F. Denning writes : — 

 " The fireball of Sunday, October 23, Sh. 12m., was 

 observed at Kenley (Surrey), llford (Essex), and in Wales, 

 as well as at other places. It appears to have passed over 

 thj sea N.E. of the mouth of the Thames at heights 

 of 84 to 40 miles. The length of the luminous course was 

 about 75 miles, and the velocity 19 miles per second- 

 Radiant near o Arietis. 



" The observation of the meteor from stations in Wales 

 is interesting, and it is probable that the object was seen 

 from a great many towns in England, for it appeared at 

 a time when many people would be out of doors. The 

 sky was, it is true, cloudy at some places and veiled the 

 brilliant light of the meteor, but it was a very fine one, 

 and gave several flashes as it slowly sailed along the 

 E.N.E. as seen from the neighbourhood of London. It 

 is important that if any further observations of an exact 

 character were made they should be published, so that the 

 flight of the object may be investigated accurately." 



The Motion of Molecules in the Tail of Halley's 

 Comet. — In a recent note in these columns (September 29, 

 p. 404) attention was directed to some results published 



