METEOROLOGY. 



583 



in Dr. Neumayer's (Hamburg) "Physical At- 

 las of the Atlantic Ocean," prepared in 1882, 

 that most of the storms in the United States 

 originate west of the Mississippi ; that many of 

 the Atlantic storms have their origin in the Gulf 

 of St. Lawrence; and that the storms of north- 

 western Europe chiefly originate in mid-Atlantic 

 and to the southwest of Ireland. The centers of 

 low pressure on these charts also point to a 

 retardation in the onward course of storms on 

 advancing over large masses of land, as happens 

 when storms approach the south of Greenland, 

 the south of the British Islands, Denmark, and 

 the Lofoden Isles. Of all storm-tracks ap- 

 proximately known in the northern hemisphere 

 the one most frequently taken is that by the 

 storms of the United States, which pursue an 

 easterly course through the Atlantic toward 

 Iceland and the North Cape. Among the 

 tracks less frequently followed, but of great 

 importance commercially and otherwise, are 

 those from New Orleans, along the east coast 

 of the United States, toward Nova Scotia; 

 from mid-Atlantic to the south of Ireland, and 

 thence through Europe to the northern shore 

 of the Mediterranean. 



A system of observations for determining 

 the height of clouds has been instituted at the 

 Upsala Observatory, Sweden. Two observers 

 with theodolites select as nearly an identical a 

 point in the cloud as they can, and take the 

 angle as nearly as possible at the same mo- 

 ment. The method is liable to serious errors 

 from the difficulty of hitting upon the same 

 point and making the observations simultane- 

 ous, which have to be allowed for. The fol- 

 lowing heights have been arrived at for the 

 several kinds of clouds : 



Stratus 625 metres. 



Nimbus (lower) 1.115 



Nimbus (higher) 2,185 



(top.. 1,690 



Cumulus and cumulo-stratus. . < base.. 1,370 



( mean. 1,438 



Lower alto-cumulus 1,988 



Higher alto-cumulus. - 4,212 



Cirro-cumulus 5,513 



Cirrus 6,823 



The authors point out that, according to 

 their observations, there are seven levels, each 

 one occupied by a different species of cloud, 

 viz.: 600, 1,100, 1,500, 2,000, 4,200-4,600, 

 5,800-6,600, and 8,000-8,600 metres ; and these 

 levels agree with those deduced by M. Vettin, 

 of Berlin, from a different mode of observation. 



Mr. H. Allen Hazen, in a communication to 

 the "American Meteorological Journal," on 

 the subject of thunder-storms, predicates that 

 they may be divided into common storms with 

 light winds, more or less rain, and generally 

 not very heavy thunder; those preceded or 

 attended by a high and sudden wind; and 

 those that may be termed electric storms, 

 mostly experienced in the West, of which little 

 has been written or is known up to the present 

 time. As to this third class, it is alleged that 

 storms occur in the West with heavy electric 

 discharges, and more or less wind, but no rain. 



These storms the Signal Service proposes to in- 

 vestigate most carefully, particularly since, if 

 it be conclusively shown that thunder-storms 

 occur unaccompanied by any rain, a contribu- 

 tion of no ordinary importance will bo made 

 to the theory of the phenomenon. 



According to the report of the Meteorologi- 

 cal Service of Canada for 1884, recent investi- 

 gations on the subject of the climatic rela- 

 tions of Canada to European countries show 

 that the Dominion has the latitudes of Italy, 

 France, Germany, Austria, the British Islands, 

 Russia, Sweden, and Norway, and has as many 

 varieties of climate as have those countries. 

 There is greater cold in winter in many of the 

 latitudes of Canada than in corresponding lati- 

 tudes in Europe, but the summers are about 

 the same. The most southern part of Canada 

 is on the same parallel as Rome, Corsica, and 

 the northern part of Spain, and it is farther 

 south than France, Lombardy, Venice, or Gen- 

 oa. The northern shores of Lake Huron are 

 in the latitude of central France; and vast 

 territories not yet surveyed lie south of the 

 parallel of those shores, where the climate is 

 favorable for all the great staples of the tem- 

 perate zone. 



In a series of photographs of lightning- 

 flashes exhibited to the Berlin Academy by 

 Dr. Kayser, the lightning is shown to have 

 gone very often from one point to several, 

 and presents an aspect, but in an inverse sense, 

 like that of a river with numerous tributaries. 

 The weak flashes did not so branch out. In 

 one remarkable effect the stem consists not 

 of one bright line only, but of four lines parallel 

 throughout, the second being rather a band, 

 and stratified transversely. Dr. Kayser be- 

 lieves that this represents an oscillating dis- 

 charge, like those which may sometimes be 

 observed by the eye in violent thunder-storms. 



The Exhibition of Instruments of the Royal 

 Meteorological Society for 1885 was devoted 

 to the exposition of sunshine recorders and 

 solar and terrestrial radiation instruments. 

 The first attempt at obtaining an instrumental 

 record of the amount of sunshine was made 

 by Mr. J. F. Campbell, of Islay, in 1853. He 

 mounted a hollow glass sphere filled with 

 acidulated water, in the center of a cup of 

 mahogany, so arranged that the sun's rays 

 were focussed on the interior of the cup and 

 burned it. The lines of burning, therefore, in- 

 dicated the existence of sunshine. Solid glass 

 spheres have been substituted for hollow ones, 

 and cards in metal frames have replaced the 

 wood ; but the principle of the instrument has 

 not essentially changed. Other modes of re- 

 cording sunshine are based on the action of 

 the actinic rays of the spectrum. Mr. J. W. 

 Clark's radiant energy recorder depends upon 

 the evaporation of water in vamo, and has the 

 advantage that its indications are readily ex- 

 pressible in heat-units. Its simplest form may 

 be represented by a modification of Wollaston's 

 cryophorus, in which the bulb containing the 



