WEATHER BUREAU. 11 



use throughout the United States. This memoir has excited very general com- 

 mendation, coupled with expressions of surprise at finding that we know so little 

 about the origin of the term and the reason for its adoption. 



(13) S. P. Langley: "The Astrophysical Observatory of the Smithsonian Insti- 

 tution." In this article Prof essor Langley first describes his bolometer and his 

 laborious, but successful, efforts to secure a holograph made by automatic meth- 

 ods. The article is illustrated by a remarkably fine reproduction of Langley "s 

 original holograph spectrum. The author calls attention to the important mete- 

 orological bearings of his studies with the bolometer. That, in fact, our seasonal 

 weather changes and probably also the irregularities of climate from year to year 

 are dependent upon the absorption of solar heat by the carbonic-acid gas and the 

 aqueous vapor in the atmosphere. The absorption is greatest in Washington in 

 August. Similar results have been attained with the actinometer of Crova at 

 Montpellier, and, especially, by the visual observations of aqtieous absorj^tion 

 lines in the spectrum, as conducted by L. E. Jewell at the Johns Hopkins Uni- 

 versity and published in 1896 in Bulletin 16 of the United States Weather Bureau. 

 There can, therefore, no longer be any doubt that by means of these instruments 

 meteorologists at sea level will be able to gauge the average and the special 

 absorptive powers of the whole atmosphere above them. The holograph and 

 actinometer must, therefore, form an important adjunct in every important 

 meteorological observatory. 



(14) F. H. Brandenburg, W. V. Brown, and Prof. E. B. Garriott: "On the clas- 

 sification and index of weather maps and weather types as an aid to forecasting." 

 These three articles on this subject have shown practicable methods of obtaining 

 an end that is greatly to be desired. Professor Garriott especially calls attention 

 to the fact that types of formations and movements of the same general character, 

 extending over periods of several days, are miich more important than types of 

 individual weather maps or weather conditions. It is to be hoped that the great 

 importance of this subject will stimulate further efforts in this line, biit they will 

 hardly attain complete success unless they are carried out in sympathy with cor- 

 rect views of the general circulation of the atmosphere. It is this latter question 

 that offers the fundamental difficulty in all weather forecasting, and especially in 

 long-range forecasts. An article by Professor Abbe in the December Review, 

 " The physical basis of long-range forecasts," explains the general character and 

 difficulties of the problem in popular langiiage, and suggests an appropriate 

 method of treating the general circulation of the atmosphere, as disturbed by the 

 presence of land and water on this globe. But the most important work on this 

 subject is that of Professor Bigelow mentioned below. 



(15) Prof. F. H. Bigelow: " Studies on the statics and kinematics of the atmos- 

 phere in the United States." 



Paper I. "A new barometric system for the United States, Canada, and the 

 West Indies." 

 Paper II. " Method of observing and discussing the motions of the atmosphere. ' ' 

 Paper III. ' " The observed circulation of the atmosphere in high and low areas. ' ' 

 Paper IV. " Review of Ferrel's and Oberbeck's theories of the local and general 

 circulations. ' " 



Paper V. ' " Relations between the general circulation and the cyclones and 

 anticyclones. ' ' 

 Paper VI. ' ' Certain mathematical formulae useful in meteorological discussions. ' ' 

 This series of papers, published in the Monthly Weather Reviews for Jan- 

 uary-June, 1902, are important contributions. They constitute a complete sum- 

 mary of Professor Bigelow's researches into the physics of the earth's atmosphere 

 and also give us a general idea of nearly all that has thus far been accomplished 

 in this field of work. This study involves a knowledge of the conditions prevail- 

 ing at and above ordinary cloud levels; therefore, the author has discussed the 

 movements of the atmosphere, the formation of cloiids. the temperatures and 

 moistiires observed by the highest balloon ascensions. He not only summarizes 

 all the work that is piiblished in detail in his International Cloud Report and his 

 System of Barometry, biit he prepares the way for a proper reduction of the 

 observations of temperature, moisture, antl wind made at Weather Bureau sta- 

 tions and for drawing of daily weather maps for several successive levels in the 

 atmosphere. He finds that with increasing altitiide above 10.000 meters the rate 

 of diminution of temperature steadily diminishes, but recognizes that the accii- 

 rate measurement of the temperature of the air in the highest strata is a very 

 difficult process, and that all efforts to secure reliable results deserve the hearty 

 support of meteorologists. 



