Mat 28, 1909] 



SCIENCE 



861 



80IENTIFI0 BOOKS 

 Annals of the Astronomical Observatory of 

 Harvard College, Edwardi C. Pickering, 

 Director. Vol. LVIH., Part HI. Obser- 

 vations and Investigations made at the Blue 

 HiU Meteorological Observatory, Massa- 

 chusetts, TJ. S. A., in the Tear 1905, Under 

 the Direction of A. Lawrence Eotch. 

 With Summaries of Observations for the 

 Lustrum and for the Twenty Tears, a Dis- 

 cussion of them. Memoirs on the Meteorol- 

 ogy of Total Solar Eclipses and on the 

 Eclipse Shadow-Bands, and a Bibliography. 

 4to. Cambridge, 1908. Pp. 147-228. Pis. 



L-n. 



The same. Vol. LXVQI., Part L Explora- 

 tion of the Air with BaUons-sondes at St. 

 Louis, and with Kites at Blue HilL By 

 H. Helm Clayton and S. P. EERaussoN. 

 The work of the Blue HiU Observatory, 

 whether it be the routine observations or the 

 original investigations carried on by members 

 of the staff, has always been of the highest 

 grade of accuracy, interest and importance. 

 The publications which have dealt with this 

 work, both those in the regular series of the 

 Annals of the Harvard College Observatory, 

 and those which have appeared in various 

 scientific journals, make up a list which in- 

 cludes some of the very best contributions to 

 meteorology. Without Professor Botch's gen- 

 erous and whole-souled support of the Blue 

 HiU Observatory, and without the steady, 

 careful and devoted work of himself and of 

 his assistants, American meteorology would 

 not occupy the important position in the world 

 of science which it does occupy to-day. This 

 statement can be made with perfect truth, and 

 without in any way whatever disparaging the 

 excellent work which has been, and is being, car- 

 ried on by the United States Weather Bureau. 

 To review, adequately, the two volumes now 

 before us is wholly out of the question in a 

 journal in which meteorology necessarily has 

 to occupy a subordinate position. We can 

 only note the most important matters pre- 

 sented in these publications. 



1. The first number of the Annals contains 

 the 1905 observations, both surface and upper 

 air, together with summaries of the observa- 

 tions at the ground during the preceding lus- 



trum and the twenty years. As Professor 

 Eotch points out in his introduction, there is 

 probably nowhere else in the United States so 

 homogeneous a series of observations, due to 

 unchanged exposure of the instruments and 

 methods of reading them. This, alone, gives 

 these records considerable importance. The 

 principal climatic features of the twenty-year 

 period are, therefore, at this time appropri- 

 ately indicated by Mr. A. L. WeUs. Mr. H. 

 H. Clayton gives an interesting sununary of 

 " The Meteorology of Total Solar EcHpses, in- 

 cluding the Eclipse of 1905." Eclipse meteor- 

 ology may almost be termed a meteorological 

 curiosity, for total solar eclipses are infre- 

 quent, and their effects are not far-reaching, 

 long-lived, or important. Practically, eclipse 

 meteorology is therefore unimportant. Theo- 

 retically, however, there is much of interest 

 in the subject. Mr. Clayton's paper gains 

 much in general usefulness because of his 

 bibliographic notes. His simimary of results 

 brings out the fall of temperature during total 

 solar eclipses, with the notable fact that, in 

 the free air and over the ocean, the time of 

 minimum; temperature occurs almost at the 

 time of totality, while over the land surfaces 

 the minimxun temperature usuaUy lags fifteen 

 to twenty minutes after totality. A low vapor 

 tension about the time of totality; a dimin- 

 ished wind velocity; an outflow of the "eclipse 

 wind," and a maximimi of pressure, all indi- 

 cate a descent of air, are aU phenomena con- 

 nected with anticyclones. The author is 

 firmly of the belief " that a cold-air cyclone is 

 generated by the faU of temperature during 

 an eclipse, and that the phenomena . . . are 

 all results of this cyclone." The final paper 

 in the first volume is one on " Eclipse Shadow- 

 Bands," by Professor A. L. Eotch. In this the 

 author gives the results which he has eoUected 

 during many years, especiaUy those obtained 

 during the eclipse of August 30, 1905. " The 

 inference from aU the data coUected is that 

 the shadow-bands are produced by the dimin- 

 ishing crescent of Hght penetrating air strata 

 differing in their thermal and hygrothermic 

 conditions, and therefore in their refracting 

 power." 



2. More general scientific interest wiU prob- 

 ably attach to the second volume, which deals 



