METEOROLOGY WATER. 217 



pressure the radioactivity reaches the maximum with the passage of the moon 

 to meridian and the minimum with the jiassajie to the opposite meridian. 



Correlation in seasonal variation of climate, (J. T. Walker {Mem. Indian 

 Met. J)ci)t., 20 (1909), pt. 6, /ip. i/7-/2//).— Correlation coefiicients based upon 

 the exponential law of distribution are worked out. 



Cirrus clouds and rainfall (Rev. Sci. [Paris]. .',7 (1909), II. Xo. 18, pp. 561, 

 562). — A direct relation between the formation of cirrus clouds and rainfall is 

 traced. 



Frost damage prevented by covers, A. G. McAdie (Mo. Weather Rev., SI 

 (1909), No. 6, pp. 22.'i, 225). — From a brief review of the evidence on the sub- 

 ject the author concludes that the use of open fires as iiracticed in California 

 orchards, for example, is not sutficient alone to protect plants under severe con- 

 ditions. "'The ideal method of frost iirotection is a (•oml)ination of a cover 

 device and a heating device." 



The cold waves of south-central Wisconsin, J. Ij. B.\rtlett (Tranfi. Wi>i. 

 Acad. ,SW., Arts, and Letters, 16 ( 1908), pi. 1, No. 3, pp. 289-306, fig. 1, charts 

 7). — The nature and causes of these cold waves are explained and it is stated 

 that " the chief damage caused by cold waves in this section is through their 

 overtaking and freezing perishable merchandise which has been shipped during 

 the preceding warm weather. Fruits, \egetables, canned goods, and liquids of 

 all kinds may be seriously damaged by very cold weather. For this reason 

 shippers of such jiroducts in the large cities watch weather conditions very 

 closely during the winter months and often hold back their shijmients until the 

 temperature is more favorable." 



Methods of obtaining advance knowledge of cold waves are explained. 

 , Biology and meteorology, (). Puochnow (Ztsc'hr. Vris-s. InHclctenhiol., 5 

 (1909) No. !), pp. 271-2111, d{jni. I). — The biological relations of meteorological 

 conditions are briefly discussed. 



Methods and apparatus for the observation and study of evaporation, C. F. 

 :Maiuin (I/O. Wcatlnr Rcr., 37 (1909), \(,s. J. /ip. l',l-li,6. pg. I; 5. pp. 182- 

 191, figs. 19). — In connection with investigations on evaporation undertaken 

 by the Weather Bureau under the supervision of F. H. Bigelow (E. S. R.. 21. 

 p. 115), the author was called upon to aid in supplying certain iustrumental 

 equipment required for the desired observations. In order to do this in a 

 satisfactory way it was necessary to examine carefully the whole problem of 

 evaporation. This article gives briefly the results of this examination as well 

 as the conclusions reached as to methods and api)aratus which seem likely to 

 lead to the most useful and accurate results. 



An annotated bibliography of evaporation, ■Mrs. (i. J. IjIvingston (Mo. 

 Weather Rev., 36 (1908), Nos. 6, pp. 18t-186; 9, pp. 301-306; 11, pp. 375-381; 37 

 (1909), Nos. 2, pp. 68-72; 3, pp. 103-109; J,, pp. 157-160; 5, pp. 193-199; 6, pp. 

 2ff8-252). — It is stated in the introduction to this bibliography that "the aim 

 of the bibliographer Jias been not merely to give a list of the titles of publica- 

 tions bearing on or referring to the subject of evaporation, but to set before the 

 reader a sufficiently full sunmiary of each reference, so far as it has been acces- 

 sible, .so that the actual work need not be consulted except in cases where the 

 fullest information is required. Articles bearing on the subject from the point 

 of view of the meteorologist, the agriculturist, the irrigation and hydraulic en- 

 gineer, have been included wherever found. Hygrometry, however, has been re- 

 garded as a distinct subject and only articles which deal with the subject in a 

 general way, or which relate it in any way to the measurement of evaporation 

 have been included. Evaporation from plants, or transpiration, has not been 

 specifically included, as that subject has been so thoroughly reviewed by Bur- 

 gerstein in Transpiration der Pflanzen." 



