532 EXPERIMENT STATION RECORD. 



formation of storms in the Northwest — definitions of the terrestrial mag- 

 netic elements — solar magnetism and its connection with the weather; 

 and practical and long-range weather forecasting. The charts show 

 tbe tracks of storms during each month of the year and some of the 

 relations existing between solar magnetism and other meteorological 

 elements. 



The principal features of the bulletin are summarized as follows: 



"(1) Tlie general circulation of the atmosphere has a downward component near 

 the poles where the northward upper stratum returns into the lower southward cur- 

 rent, its power consisting in slowing flown the rapid eastward drift by diverting it. 

 into descending anticy clonic vortices; (2) these are localized upon the continents, 

 chiefly in winter, by reason of the action of the land areas being colder than the 

 oceans, wherefore highs tend to form in western Canada especially during that 

 season; (3) the entrance of the earth into longitudes of the sun having a stronger 

 magnetic held lowers the temperature in this region, and thus assists the tendency 

 to form high areas at definite dates in the general subpolar circulation, it being 

 more pronounced on the North American continent than elsewhere in the same high 

 latitudes by reason of the presence of the magnetic pole near that place; (i) these 

 hi<;hs drift southward and eastward within the great eastward upper current, being 

 still fed by the general circulation, which itself is sustained from the tropical zones 

 and continues to discharge downward into the highs by means of an anticyclonic 

 stationary system of streams ; (5) between successive highs is formed a low with 

 cyclonic circulation, which, under hydrostatic pressure, aided by convectional ver- 

 tical components of warmer air, drives the air in stream lines back into tho upper 

 strata, there to be aimlessly destroyed in the rapid eastward currents; (6) the cou- 

 vective action in cyclones derived from local temperature and the latent heat of 

 condensation of vapor in precipitation is an important incident, assisting gyratory 

 vortex action, but after all only a secondary phenomenon; (7) this view admits the 

 validity of Ferrel's analytical solution (also Overbeck's) of the general circulation 

 of the atmosphere, but concludes that it is not strictly applicable to the local mid- 

 latitude cyclones; that the general cyclone of the poles and the local cyclone with 

 anticyclone surrounding it are not so parallel in theory as was supposed in the 

 formula'. On the other hand, the lows are not eddies in the upper currents, but 

 more properly the highs are the the eddies; actually they are stationary downward 

 circulations in deflecting the direction of the upper into the lower strata, and the 

 lows are secondary effects derived from these under the impelling forces of gravity 

 and hydrostatic pressure. This explanation gives to the entire machinery of the 

 atmosphere, it is believed, a logical and harmonious operation, and it certainly 

 avoids some of the difficulties that are now felt by meteorologists." 



Experiments on the prevention of night frosts, F. H. King 

 ( Wisconsin Ma. Rpt. 1896, pp. 207-209, fig. ;.'). — In continuation aud 

 extension of the experiments of tbe previous year with torches, 1 a plat 

 of rape was furrow irrigated on the night of September 27, when tbe 

 temperature early in tbe evening bad been as low as 40° F. Tbe tem- 

 perature of tbe lake water as it reached the field was 56° V. • at the 

 lower end of tbe rows it bad fallen to 54° F. 



"Not only did frost form after the water was brought to the areas, but some 

 of the rape leaves became still' with streams of water flowing both sides of the 

 row. . . . Close to the water, however, the leaves did not become so rigid as to 

 break in the hand, while at a distance from the water they did." 



1 Wisconsin Sta. Rpt, 1895. p. 253 (E. S. R., 8, p. tiTl I. 



