374 



KXOWLMDGK. 



OcTdr.EU. Uni. 



The imjiortant work carried out through balloons 

 is of the more interest to ourselves, since for thirt\' 

 years the originator of scientific upper air explora- 

 tion In- this means. John Glaisher, lived in our 

 midst. True, a small beginning had alread}" been 

 made in 1852 b\ Mr. Welsh, of the Kew Observatory. 

 In 185iS, the British .\ssociation appointed a com- 

 mittee to investigate decrease of tem[)erature with 

 altitude, but it practicalK' did nothing. A new 

 committee, appointed in 1.S61. included Admiral 

 Fitzrox'. Airv, Brewster. Herschel, Tyndall and 

 Glaisher. After disheartening failures the generositx' 

 of ("oxwell came to its rescue by offering to build a 

 balloon for their use. Mr. Glaisher responded to 

 this enthusiasm hv determining himself to make 

 the observations. Thus began in 1iS(j2 the famous 

 ascents b\" which for the first time ai)pr(>ximatel\' 

 correct data were obtained for what we may call the 

 middle region of the atmosphere at present accessible 

 for meteorological records. In the course of three 

 vears a height of eleven thousand feet, or over two 

 miles, was exceeded on no less than eleven 

 occasions, including that most famous ascent from 

 Wolverhampton, on September 5th, 1862, to the 

 unprecedented height of about seven miles, when Mr. 

 Glaisher became unconscious and Coxwell, with 

 hands frozen, barel\- succeeded in pulling the valve 

 cord w ith his teeth. This height has probably ne\er 

 been surpassed b\' an\ balloonist of later \ears. 

 But no observations were taken above about thirty- 

 one thousand feet, whereas, in 1901, Berson in 

 Germany took records to nearly thirty-fix e thousand 

 five hundred feet. In this case both nun became 

 iniconscious, onl\- reviving when the\' had fallen 

 two-and-a-half miles. In 1875, two out of three 

 French meteorologists were suffocated at a height 

 considerably less. 



These disconcerting consequences indicated only 

 too plainlv that direct observation b\' manned 

 balloons was only possible ui) to six, or, at most, 

 seven miles, and that but rarely, at immense cost. 

 This has led to the present development of free 

 balloons, or bullous sondes, a method alreadv 

 suggested hx Le \"errier in 1874. It had. indeed, 

 been (juickly acted upon, but onh' in the form of 

 pilot balloons, to determine wind direction and height 

 of clouds, and by these, from 1877 onwards, much 

 valuable knowledge was secured. 



While balloon work was thusde\eloping, ad\ances 

 of eijual importance were made by means of kites. 

 In 18.SJ, E. D. Archibald first used piano-wire in 

 experiments on wind velocitw His liiram's anemo- 

 meter was. perhaps, the first recording instrument 

 employed in Upper Air research, but it only ga\e 

 the total from beginning to end. Two years later 

 began the splendid series of observations which has 

 made the Blue Hill, in Massachusetts, a household 



word wherever meteorologx' is f(_)llowed : and here 

 it was. in 1890, that William A. Eddy devised a 

 iorxw of tailless Malaw or — as we used to call them 

 at school — Dutch kite, which now, as the l)o\-kite. 

 has superseded all others. .\t Blue Hill again, four 

 years later, was sent up the first continuoush' 

 recording instrument, and from this date progress 

 was rapid and wide-spreading, for, in 1898, th? 

 ni_'\\ K-founded International Aeronautical ("oni- 

 niittee was alread\' recommending similar work 

 U)v all stations of the first class, advice which was 

 adopted in France and Russia. Work in England 

 was initiated bv Mr. W. H. Dines, especially with 

 flights from tug and shore on the west coast of 

 Scotland in 1902, work since continued for the 

 Meteorological Office, in association with Inilloiis 

 soiulcs, first at Oxshott, since at Pyrtoii Hill, in 

 Oxfordshire. To him, perhaps, more than to an\- 

 other person, Englanil is indebted for her present 

 good position in this new field f)f eX[)loration. 

 The famous French sa\ant. howe\er, M, Teisserenc 

 de Bort, first achieved a height of over a mile, by a 

 kite flown from a Danish gunboat in the l:5altic, a 

 height which now has in some instances been nearly 

 trclilcd. It was not long before our ISritish Office 

 added Upper Air records to its weckK' weathe ' 

 reports, as thev were taken at Glossop, Pyrton Hill, 

 Ditcham Park and Brighton. At the lirst station, 

 under the supervision of Manchester Uni\ersity. daily 

 records are made, as far as jiossible supplemented 

 by balloons when the wind is deficient. 



I>ut kites are, of course, strictlv limited in height 

 of ascent, and it is with pilot balloons and ballon 

 sondes* that the recent extraordinar\- success in 

 obtaining extensive series of records at heights up to 

 and abo\e ten miles have been secured. Thirteen 

 to fourteen miles is perhaps the present thoroughly 

 ascertained limit.'' These ascents are made b\' 

 means of rubber balloons, usualh' weighing half a 

 pound and about half a metre across, filled with 

 hydrogen and used either singly (sometimes with a 

 parachute), or else in pairs. They are filled sufficiently 

 to burst at a given elevation (one only in the case of 

 a [)air, when the other acts as a parachute for the 

 combination) and carr\- special recording apparatus, 

 carefulh' guarded against rough shocks \\hen 

 striking ground again. The heights, when possible, 

 are determined bv one or more theodolites to check 

 the aneroidogram record, on which alone, more 

 frequentlw the observations have to depend. 



Besides more sporadic work concerted observations 

 have, since 1901, been made on the first Tuesdax' of 

 each month b\- nearh' all Euro()ean countries. To 

 the instruments is attached a ticket w ith instructions 

 to the finder and the offer of a reward for its return. 

 As a rule more than half those sent up are so recovered, 

 sometimes after a flight of owv two hundred miles. 



'■' A pilot balloon gives wind directions at \ar\in,i; lieights by theodolite observations ; the name, " sounding balloon " is 



applied inoir iisnall\' to ballonets with recording instruments. 



I Some English records ha\'e been obtained almost certainly for at least fifteen miles; but the values above twelve miles 



are subject to serious possibilities of altitude error. 



