610 



SCIENCE. 



[Vol. L, No. 21. 



Mean annual temperature range, I Toronto, Canada, 

 cloudiness, ) ' 



with sun-spot numbers. 



If these figures be projected in curves, it will be 

 seen that minhnum ranges occur markedly about 

 1S4S and 1859, while maximum ranges occur about 

 lSi4 and 185.5; which are just the epochs of maxi- 

 mum and minhnum sun-spot numbers respectively. 

 Making full allowance for varying cloudiness, we 

 still do not obtain any different results. The whole 

 subject needs complete investigation. — {Rep. com. 

 solar phys. London, 1882. ) H. A. ii. [1156 



Applications of photography to meteorology. 

 — Photography is constantly finding new applica- 

 tions in the other sciences. By its means, under 

 the direction of Capt. Abney, experiments are being 

 conducted at Kew, Eng., to determine the height 

 and velocity of clouds. Two similar cameras are 

 set up at a distance of about six hundred feet apart, 

 and provided with instantaneous shutters, which 

 can be released at the same instant by electricity. 

 By knowing the angle of inclination of the cam- 

 era', and measuring the position of the cloud as 

 photographed on the two plates, we at once have a 

 trigonometrical observation which will give us the 

 distance of the cloud with great accuracy. The 

 axis of a cyclone is probably not vertical, its upper 

 portion being in advance of the lower in relation 

 to the direction in which the cyclone is moving: 

 hence the higher clouds are sometimes affected by 

 an approaching storm before its influence affects 

 the winds blowing at the surface of the earth. The 

 cirrus clouds are, therefore, the ones to whose ob- 

 servation is attached the greatest importance. Occa- 

 sional observations only have so far been made, but 

 the Meteorological council has under consideration 

 the plan of adopting the instrument for continuous 

 use at its central station at Kew. Tlie observations 

 made so far would seem to indicate that the cirrus 

 clouds are not situated at so great an elevation as 

 has heretofore generally been supposed. — {Brit, 

 journ. phot.. May 4.) w. n. p. [1157 



PHYSICAL GEOGRAPHY. 

 Old river-courses by Vicenza and Padua. — 



F. Molon gives geological and historical evidence to 

 show considerable changes in the rivers Astico and 

 Brenta, on the northern margin of the plain of Lom- 

 bardy, in post-glacial times. On issuing from the 



mountains, both of these streams formerly turned 

 westward, toward a depression produced by an old 

 fault running along the eastern margin of the hills 

 from Schio to Vicenza; but, as this district was raised 

 by their deposits, they ran more directly south, and 

 now the Astico is laying its sands on the old beds of 

 the Brenta, wliile the latter has abandoned the chan- 

 nel which led it through or even west of Padua, and 

 flows farther east. By such diversions from old chan- 

 nels, the volume of some of the lower streams has 

 been greatly affected. The name Retrone was formerly 

 applied to a river of considerable size, extending to 

 Padua ; but it is now limited to a small stream west 

 of Vicenza. The Bacchiglione, an Italian corruption 

 of the German Bachlein, was named when its size 

 justified its meaning; but it has now usurped the 

 place and volume of the old Retrone. — (Atti ist. ve- 

 neto, i. 1882-83, 247, -347. ) w. m. d. [1158 



Origin of fiords. — Fr. Ratzel calls attention to 

 the broken form of polar coasts in both hemispheres, 

 and tlie bare, rocky surface of the adjoining lands, 

 and concludes that both of these characteristics re- 

 sult from tlie strong erosive action of ice. He lays 

 the excavation of not only our Great Lakes and 

 Onega and L'adoga to the same cause, but the Baltic, 

 the North Sea, and Hudson's Bay as well (Ausland, 

 1883, 223, 2.54). The barrenness of polar lands may 

 well be ascribed to ice-action, wliich has undoubt- 

 edly produced some modification of the surface as 

 well; but to consider all their diversity of form due 

 to glacial erosion exaggerates the power and dura- 

 tion of the ice as greatly as it neglects other and 

 eflScient causes. — w. M. D. [1159 



GEOGEAPHY. 



(Arctic) 

 Northern voyages in the fourteenth century. 



— Baron Nordenskiold has begun the publication, 

 under the title of 'Studier ochforskniagar,' of a popu- 

 lar scientific account of early voyages to the liigh 

 north, as a sort of supplement to tlie ' Voyage of the 

 Vega,' in whicli so many early northeastward voy- 

 ages were noticed. The first volume contains an 

 account and discussion of the voyages of the brothers 

 Antonio and Nicolo Zeno of Venice, who are sup- 

 posed to liave journeyed to the Faeroe Islands, Ice- 

 land, and East Greenland toward the close of the 

 fourteenth century. The author brings forward 

 reasons for believing that the voyages were actually 

 made, and the narrative authentic, a general dis- 

 belief in them having been (with a few individual ex- 

 ceptions) hitherto prevalent. The volume contains a 

 photograpliic reproduction of the map of Claudius 

 -Clavus in 1427, — a remarkable discovery by Norden- 

 skiold himself, who found it in the city library of 

 Nancy, included in an old manuscript copy of Ptole- 

 my's Cosmographia. The period when all early voy- 

 ages were regarded witli suspicion or open disbelief 

 seems to have passed away, and the truthfulness of 

 some of them is established; while the misapplication 

 of others (as the Chinese voyages to Fu-sang, now 

 known to be a province of Japan, but formerly inter- 

 preted by enthusiastic geographers as north-west 

 America) has been rectified. The danger of running 

 into tlie opposite extreme of credulity is not, liow- 

 ever, to be overlooked, in view of the attention wliich 

 the perfectly preposterous story of ' Moncatch-Ap6 ' 

 has recently received from a few serious students. 

 It is not necessary to say to any ethnologist who 

 understands the nature of tlie races of north-west 

 America as they were wlien discovered, that the story 

 referred to is not less improbable than the wildest 

 vagaries of Jules Verne. — w. H. D. [1160 



