500 



NATURE 



[July 17, 1913 



this met with no acceptance was doubtless due 

 to the improved knowledge of the motions of the 

 planets in the third century, when it was found 

 that there were other irregularities which could 

 not be accounted for by assuming the earth to be 

 in motion. 



The book of Aristarchus, now for the first time 

 translated into English, is of great interest to the 

 mathematician because the ratios of the sizes and 

 distances which he calculates are really trigono- 

 metrical ratios, sines, cosines, &c, although at 

 the time when the book was written trigonometry 

 had not been invented, and no close approximation 

 to the value of tt was known. Aristarchus there- 

 fore endeavours to find upper and lower limits 

 for those ratios by assuming propositions com- 

 paring the ratio between a greater and a smaller 

 angle in a figure with the ratio between two 

 straight lines in the figure. These propositions 

 were afterwards proved by Ptolemy. To the 

 astronomer the book is particularly interesting by 

 the attempt made by Aristarchus to determine 

 the ratio of the distances of sun and moon by 

 observing their angular distance at the time when 

 the moon was half illuminated. The very erro- 

 neous result found (19: 1), corresponding to a 

 solar parallax of 3', continued to be accepted from 

 the time of Ptolemy to that of Kepler. 



J. L. E. D. 



THE APOTHEOSIS OF THE POTATO. 



(1) The Potato: A Compilation of Information 

 from Every Available Source. By E. H. Grubb 

 and W. S. Guilford. Pp. vii + 545. (London: 

 Constable and Co., Ltd., 1913) Price 8s. 6d. 

 net. 



(2) Commercial Gardening: A Practical and 

 Scientific Treatise for Market Gardeners, 

 Market Growers, Fruit, Flower and Vegetable 

 Gro-wers, Nurserymen, &c. By many practical 

 Specialists, under the Editorship of John 

 Weathers. In four volumes. Vol. i., pp. xiii 

 + 239 + plates; vol. ii., pp. xii + 235 + plates ; 

 vol. iii., pp. xii + 240 + plates ; vol. iv. , pp. xii 

 — 244 -(-plates. (London: The Gresham Pub- 

 lishing Co., 191 3.) Price 36s. net, the four 

 volumes. 



'HERE are men who, having attained to 

 wealth and fame by the agency of some 

 humble instrument, basely repudiate and kick over 

 the ladder by which they have risen. Not so the 

 authors of the first book on our list. The potato 

 has "made" them, and in return they proceed 

 to "make" the potato. A large number of men 

 have at times written about this vegetable, and 

 extracts from their books and papers occupy a 

 NO. 228l, VOL. Oil 



(1) nr 



very large proportion of the volume. The food 

 value, methods of propagating, cultivating, har- 

 vesting, and selling, all receive attention, but the 

 authors are so evidently enthusiastic, and dis- 

 course so eloquently on the merits of their subject, 

 that we are carried along with them, and forget 

 that, after all, they are only talking about potatoes, 

 and not about alpine plants or roses. 



The book makes one realise, as nothing else 

 we know has quite done, how manifold are the 

 aspects from which a simple natural object can 

 be regarded. Successive chapters give long 

 quotations from the writings of chemists, botan- 

 ists, zoologists, entomologists, mycologists, agri- 

 culturists, engineers, economists, legislators, 

 business men, doctors, historians, geographers, all 

 dealing with problems directly and closely con- 

 nected with the potato. And the senior author 

 shows us enough of his personality to let us see 

 how entirely enthusiastic the plant-fancier may 

 become over this plant. There is nothing critical 

 about the book, and the student of science may 

 not find much of direct value to him. Perhaps 

 its main interest to the general reader is that it 

 deals with one of the humblest products of the 

 garden in the same enthusiastic and affectionate 

 spirit as Dean Hole wrote about roses, or Farrar 

 about "alpines." 



(2) The four volumes on commercial gardening 

 represent a somewhat ambitious attempt to put 

 into one work the rather wide knowledge that the 

 successful grower ought to have of crops, 

 manures, markets, &c. ; they are frankly intended 

 for the commercial man only. Had they been con- 

 fined to practical matters we should have found 

 little fault with them, but the scope has been 

 widened, and chapters on "science" have been in- 

 serted. It might be argued that sound science 

 could not fail to be useful to the grower; on the 

 other hand, it might also be argued that the 

 busy grower has no time to concern himself with 

 the reasons for things, but simply wants specific, 

 trustworthy information on his problems. Either 

 plan might have been adopted and justified. But 

 we do not see any justification for the third plan 

 that has been followed of putting in poor science. 

 While a first-hand knowledge seems to have been 

 expected of the writers on practical subjects, no 

 such qualification seems to have been deemed 

 necessary in the case of science. We are not 

 referring, of course, to Mr. Massie's and Mr. 

 Theobald's contributions, or to some of the botani- 

 cal work, which is also good, but the large 

 sections on science are in the main distinctly 

 poor. Some of the errors are ludicrous, and 

 could have been corrected by any good student 

 at an agricultural college. The distinction between 



