June 22, 1916] 



NATURE 



34^ 



The temples are quadrangular structures enclosing 

 one or more courts open to the sky, and ihey all 

 agree in having the eastward side more or less north 

 of east, the western side facing south of west. But 

 the orientation varies considerably. Thus while the 

 Temple of Ishtar is oriented almost due N. and S. 

 and E. and W., facing only about 4° N. of E., 

 the Temple of Ninib faces about 20° N. of E., and 

 the Temple of Ninmakh some 25° N. of E. This 

 latter temple has its entrance on the northerly side, 

 and the shrine on the southern, whereas the Temple 

 of Ishtar has entrances on the E. and S. sides, and 

 '•e shrine on the W. The figures given are approxi- 



ate only. 



Dr. King is now at work on the third volume of 

 his "History," each volume treating of a separate 

 period, and being to some extent independent of the 

 others. When completed the work will be of lasting 

 value, although each year adds fresh knowledge from 

 new discoveries. Dr. King teaches us much, but he 

 also makes us feel how much there is to learn. What 

 principles, for instance, guided the Babylonian archi- 

 tects and builders in the orientation of their temples? 



June 12. H. K. 



" Ptolemy's Catalogue of Stars." 



M.\Y I point out that your reviewer of "Ptolemy's 

 Catalogue of Stars" (June i, p. 282) is mistaken in 

 suggesting that a mere confusion between the uncial 

 alpha ( = 1) and the uncial delta ( = 4) will account for 

 Ptolemy's assignment of the first magnitude to what 

 is now the third-magnitude star, B Eridani? 



The star, called " the last in the River," whence the 

 Arabic name of Achernar, is expressly described in 

 the catalogue as "brilliant," XauTrpdj, an epithet ap- 

 plied to no other in the group. And in another work 

 of Ptolemy's, the '^afrns, in which the risings and 

 settings of thirt\- " fundamental " stars, fifteen of 

 the first magnitude and fifteen of the second, are 

 calculated for several parallels of latitude, "the last 

 of the River " takes its place among those of the 

 first magnitude. 



Moreover, the same star is mentioned several times 

 by Hipparchus in his one surviving work, the com- 

 mentary on Aratus, and in each case it is described 

 a^ the brightest in the constellation of the River, 

 \\ hich it. could not have been had it been of the fourth 

 magnitude only. 



Again, the star is of the first magnitude to Al Sufi, 

 whose catalogue was drawn up, 800 years after 

 Ptolemy, for the express purpose of revising the 

 magnitudes given in the Almagest. Al Sufi adds 

 some particulars as to its position which alone would 

 suffice to refute the wild suggestion that the star 

 meant was. not 6, but the modern a Eridani, Acher- 

 nar, a star invisible to Greek and Arab astronomers. 



There can be no reasonable doubt that B Eridani 

 has declined in lustre, from the first magnitude to 

 the third, in the interval between Al Sufi and the 

 (lavs when, during the early Portuguese voyages, it 

 again was seen, after many centuries, by European 

 eyes. That Ulugh Beg, 1437, should still make it a 

 first-magnitude star is remarkable, but not conclu- 

 sive, as his work was a revision of the places only, 

 not the magnitudes, assigned to the stars by his pre- 

 decessors. E. J. Webb. 



Noke, IsHp, Oxford. • 



The suggestion was not made by the reviewer, but 

 is made in the work under review (p. no), where it 

 is stated that "it is most probable that in a very 



NO. 2434, VOL. 97] 



ancient manuscript the delta = 4 was erroneously taken 

 to be an alpha=i, of which the present investigation 

 shows numerous examples." As regards the state- 

 ments of Hipparchus, Ptolemy, and Sufi, the facts 

 are : — 



Eridaiii 



Hipparchus, Rhodes 

 Ptolemy, Alexandria 

 Sufi, Bagdad 



Shiraz 



Teheran 



Lat. 



+ 36 

 + 31 

 + 33 

 + 30 

 + 35 



Decl. 



-50 

 -48 



-45 



-45 

 -45 



Zen. dUt. 



. 86 



• 79 

 . 78 



• 75 

 . 80 



Sufi, on account of the low altitude, took the mag- 

 nitude from Ptolemy. That Q Eridani was of the 

 first magnitude for more than a thousand years, and 

 from the time of Halley (1677) to the present dav of 

 uniform brightness (3 or 4 mag.), without sign of 

 variability, will scarcely be accepted by astronomers. 



The Reviewer. 



MeteorologicaJ Conditions of a Blizzard. 



Your correspondents are entirely right in their con- 

 tention that, in this country, the word "blizzard" is 

 used as a rule quite wrongly. I have protested many 

 times in the past against this misuse. 



For various reasons, a true blizzard cannot occur in 

 Britain. In the first place, as several correspondents 

 have already pointed out, the necessary climatic condi- 

 tions are lacking; for a wind of extremely high velo- 

 city never occurs here in conjunction with sufficiently 

 intense cold, producing fine dry powdery driving snow. 

 Secondly, a wind-velocity sufficiently high to produce 

 a blizzard is seldom or never attained, except in a 

 region marked by an immense extent of level surface, 

 little broken by trees and other obstructions, and there 

 is no such region in Britain. All the necessary condi- 

 tions, both climatic and physical, exist, however, in 

 that true home of the blizzard — the vast plains and 

 prairies lying to the east of the Rocky Mountains, in 

 Central North America, especially in Dakota and 

 Manitoba. Even the great EngAsh snowstorm of 

 January 18, 188 1 (which I remember very well indeed), 

 bore little resemblance to a true blizzard, for the 

 intense cold and high wind-velocity characteristic of a 

 blizzard were both absent. 



Those interested in the subject could not do better 

 than refer to a little work, " Manitoba Described," 

 which I published in 1885, after a visit to 

 that countr}-. Therein will be found (pp. 57-58) 

 an excellent description of a Manitoban blizzard, 

 written by my friend Mr. Ernest Thompson Seton, 

 then living there. It was, I believe, the earliest de- 

 scription ever published, at all events in this countr}'. 

 Moreover, its graphic style has never been, and could 

 not be, excelled. 



It may be worth mentioning — though the pohitjs of 

 etymological rather than of scientific interest— that the 

 use of the word "blizzard" in the above-mentioned 

 article (1885) marked, I believe, its first appearance in 

 permanent literature in this country, though there are 

 instances of its use three or four years earlier in Eng- 

 lish periodical literature. Earlier than that the word 

 cannot have been used anywhere in the sense in ques- 

 tion ; for it did not make its appearance, even in 

 American journalism, before, the winter of 1880-81. 



Miller Christy. 



Broom Wood Lodge, Chignal St. James, 

 Chelmsford, Juneis-" 



