47.; 



MKTKni;<Lo<;Y. 



He thinks that for a large part of the year fore- 

 cast* of temperature. on the assumption of regu- 

 lar rhythmic oscillations and a knowledge of the 

 theirU'ginning and end ing, may be made 

 foraweek or two in advance with nearly as much 

 accuracy as they are now made by the Weather 

 lluivai! for thir irs. 



In t he discussion of a table of moan monthly 

 and annual temiH-ratures for London UK-: 



hundred ami thirty years. 17W-1892, 



lr. A. Buchan says that much labor has been 



Marching for evidence of cycles, but it 



t be said that the results show more than 



highly interesting resemblances and contrasts 



among the months, and that in whate\ er way t he 



periods are \ :! they suggest no appearance 



r.ni a tendency is shown of types of 



high an<i low (ampmtavB to prolong themselves 



during tn<iths. seasons, and years. 



Some interesting results have been obtained in 

 H.-rlin "f meteorographs sot up in the 



** Urania" pillars. Kach pillar contained a ther- 

 mograph, a barograph, and a hygrograph. placed 

 . side in a metal case through which a rapid 

 current of air was kept up. The observations 

 showed that the temj>eratures recorded on 'J 

 closely adjacent pillars may differ by one de- 

 gree or more both on a warm summer day and 

 in the coldest weather. In one case the air was 

 found to be warmed by the adjacent row of 

 houses exposed to direct sunlight. In another 

 the radiation was observed to be greater opposite 

 a gateway than in the street The very consid- 

 erable local differences of air tempi-nit "iv re- 

 corded on closely neiirhl > <rinu r pillars could hardly 

 have been expected a pri 



For determining temperature and humidity 

 near a surface of snow Dr. SQring placed a ther- 

 mometer on the snow and another at the usual 

 above the surface, either exposed or pro- 

 tected, while an aspiration thermometer, placed 

 1 centimetre above the snow, recorded the tem- 

 perature of the air. The temperature recorded 

 thermometer proved to be considerably 

 influenced by its size, shape, and position, as 

 well as by the condition of the snow surface, etc. 

 The observations were therefore restricted to the 

 i ination of the difference between the tem- 

 perature of the snow and that of the air above 

 it, as related to clouds and the motion and tem- 

 perature of the atmosphere. The difference was 

 lessened as the sky became more clouded, and 

 when the clouding was complete, during a fall 

 of snow, the temperature of the snow's surface 

 was higher than that of the air. The difference 

 became greater as the temperature fell, but was 

 lesstntd as the motion of the air became more 

 rapid. As t" th- influence of the snow surface 

 on the humidity of the air, the author has ar- 

 imd at the result that evaporation from the 

 now is much more frequent than condensation 

 from the air, but that they are about equal in 

 amount 



The thermophone. an instrument for ru 

 ing temperature* at distant or inaccessible places, 

 was devised by H. E. Warren and O. ('. Whipple 

 for the purpose of obtaining the temperature of 

 UH. water at the bottom of a pond. It is also 

 suitable for obtaining the temperature of the 

 soil at various depths. The apparatus resembles 

 thermometer; advantage 



is taken ( .f the fart that different metals havr 



different electrical temperature c.-ellieici 

 I lax ing compared the ! 



and Silesia with tt, 



ires, rainfall, and in: 



fifteen yeai --ner found that the 



of temperature corresponded with tin 

 crops in both provinces ox< -ept in 

 the curves.. f rain fall showed no sue! i 

 ence in I :h they were in 



greater harmony in - The curves 



v of rain were in somewhat closer 

 ance with those of the crops than were ' 

 rainfall. The author's final concl 



.ationshipof weath.r to cn. 

 much more thorough investigation than 

 siblc with the scanty data as yet available. 



Clovti. Discussing the questi 



cl.mds are composed of hollow ves;< 



globules. M. Van der .Men-l.rn | &&-] 



periment performed by .Joseph Plateau in ittj 



in which a column of water nearly three <jiiar- 



ters of an inch in diameter was- >\\\ 



glass tube closed at the top but pen at 



toiu. Beneath the open >urface of the HHI 



was a vessel of boiling water, from which a cur 



rent of visible vapor rose continnalh 



pended liquid never lost its compl. 



ency under these conditions, not with- 1 



the number of spherules of vapor that roteJ 



provided the outside of the tube \\; 



This seemed to prove that the vapor v. 



composed of spherules filled with air. but 



globules, and constitutes a strong are; 



against the theory that the clouds are I^^H 



tute-1 of vesicles. Other considi-rat i 



in the same direction are theoretical. 



spherules are very small, they will be mor- 



sustained in the air if they are surround' 



very thin layer, the density of which din. 



toward the exterior, and" which. ;, 



Lord Kelvin's principle, they will . 



more rapidly the more minute they are. Ej^H 



the other hand, the globules of t'l 



relatively large, they will obey their 



in falling will traverse strata of air, 



constantly wanner, and will con-e.juently 



rate more and more rapidly, till tl 



is reduced to a measure at which their 



fall is opposed by the resistance of the 



is therefore not necessary to suppose lai 



smaller spherules filled with air to ej 



suspension of clouds in the aimo-ph- 



more, this suspension is only re! a' 



clouds are almost constantly oh 



fact which proves either that < 



ing on, or that some of the parts of 



are constituted are falling. 



In a lecture on the" Physical Pheimmei;. 

 Upper Regions of the Atmosphere/ 1 Prof. 

 Cornu compared the atmosphere to an i 

 thenno-dynamic engine, in which the M. 

 source of heat and intcrplan. 

 condenser. The most intere- 

 take place in the more inaccessible j 

 atmosphere, and though the dilVici. 



information about these elev.v : -' 

 are great, the physicist is begin ni 

 much of the real explanation of natural ph f> 

 nomena, and is even able to reproduce t 

 his laboratory. Among the unexpected stati< 



