iU DEPARTMENTAL REPORTS. 



hypotheses, especially that which referred them l)ack to the Glacial age, must 

 now be abandoned. 



(5) H. H. Kimball: "■ The general circulation of the atmosphere," especially in 

 the Arctic regions. In this memoir, which was a thesis for the degree of M. S., 

 the author shows the great contrast between the theories of Ferrel, Oberbeck, 

 and Helmholtz on the one hand, and those of Bigelow and Teisserenc de Bort on 

 the other. He then collects and charts all available observations of the move- 

 ments of the highest cirrus clouds in northern latitudes, and shows that they 

 demonstrate the existence of a rather weak movement of the surface wind west- 

 ward for latitiides north of 65°, with modifications introduced by the low baro- 

 metric pressures in the North Atlantic and Bering Sea. It is probable that these 

 modifications are appreciable, because in northern latitudes the cirri are low 

 down, and above these there should be a stronger ciirrent from the west eastward. 



(6) Prof. C. F. Marvin: " The measurement of sunshine and the preliminary 

 examination of Angstrom's pyrheliometer. " This paper not only introduced 

 Angstrom's electric compensation pyrheliometer to the attention of American 

 physicists, but shows how it can be best used to advance meteorological research. 

 Three copies of this instrument have been purchased by the Weather Bureau and 

 carefully compared before being intrusted to the hands of the respective observers. 

 Professor Marvin's paper gives the results of these comparisons, from which it 

 appears that the amount of heat received from the sun per minute, per square 

 centimeter, by a surface normal to the solar rays and outside of the earth's atmos- 

 phere, is about 3.1 gram calories, and that measurements made at sea level are 

 liable to an lancertainty of aboiit 1 per cent. 



(7) O. L. Fassig: " The westward movement of the daily barometric wave." 

 This is a short article accompanied by important charts, showing that the princi- 

 pal features in the diurnal curve of local variations of barometric pressure move 

 westward around the globe daily. 



(8) , (9) Mark S. W. Jefferson: ' ' The reduction of records of rain gauges. ' ' This 

 article calls attention to the unsatisfactory condition of our knowledge of the dis- 

 tribution of rainfall. The author suggests certain modifications in the methods of 

 preparing rainfall charts. As this subject is of the greatest interest in relation 

 to agi'iculture, irrigation, engineering, and general meteorology, correspondence 

 was invited on this subject. Professor Abbe prepared an extensive ' ' symposium ' ' 

 on "Rainfall and charts of rainfall," which appeared as a supplement to the 

 Monthly Weather Review for April, 1902. In this symposium the latest rainfall 

 charts by Prof. A. J. Henry, of the United States Weather Bureau, for the years 

 1871-1901, inclusive, and by Mr. Henry Gannett, of the United States Geological 

 Survey, for the years 1871-1893, appeared, accompanied by a relief map of the 

 United States, which must be studied in connection with the rainfall. The cor- 

 respondence and extracts published in this symposium explain the methods of 

 preparing rainfall charts, and show some of the errors of those who would apply 

 hypothetical corrections for altitude, or would, from the presence of forests and 

 lakes, infer a special increase of rainfall. The whole discussion emphasizes the 

 extreme importance of a large increase in the niimber of oiir rainfall stations, in 

 order that the Weather Bureavi may satisfactorily respond to the general public 

 demand for information as to rainfall and snowfall. 



(10) Maxwell Hall: "The sun-spot period and the temperature and rainfall of 

 Jamaica." In this paper the author shows that since 1883 there has been a close 

 parallelism between the mean maximum temperatures at Kingston and the curve 

 of sun-spot numbers. There is also some show of parallelism between this sun- 

 spot curve and that of the general rainfall for Jamaica. 



(11) A. Wolfer: In order to facilitate the study of solar relations. Professor 

 Abbe reprinted in the Monthly Weather Review for November, 1901, the complete 

 table of •• Wolf's relative sun-spot numbers." This led to a correspoiidence with 

 Prof. A. Wolfer, of Zurich, who stated that, as the successor to Professor Wolf, 

 he had undertaken to revise the original series of sun-spot numbers and incor- 

 porate all newly discovered data. This revision was, therefore, published with 

 some remarks by Wolfer in the Monthly Weather Review for April, 1903, simul- 

 taneously with its puljlication in Switzerland. This constitutes a most welcome 

 addition to our knowledge of sun-spot phenomena, and while, on the one hand, it 

 will undoubtedly stimulate research into the relations between the sun and the 

 earth, it will, on the other hand, serve to refute many erroneous hypotheses and 

 bring its nearer to the trvith. 



(12) Albert Matthews: *• Indian summer." This is the result of an exhaustive 

 search in the literatiire of England and America; the aiithor shows that the term 

 Indian summer first appeared in 1794, at which time it was jirobably in general 



