May 28, 1908] 



NATURE 



/J 



tide. It is thus obvious that this tide must be entirety 

 masked by chang^es of sea-level arising from meteor- 

 ological causes." 



We cannot help thinking that the methods of har- 

 monic analysis described on pp. 157-258 are a little 

 unnecessarily cumbrous. One simplification we should 

 like to suggest. Given the height of the tide at in- 

 tervals of one solar hour, an approximate period 

 exactly commensurable with a solar hour might 

 always be taken for the tide under analysis. The 

 difference between the true period and the assumed 

 period will then appear as a progressive change of 

 epoch in the successive periods of analysis ; mean- 

 while the assumed period, involving exact repetition 

 after an integral number of hours, immensely facili- 

 tates the harmonic analysis, as the present writer has 

 found in atij allied subject. 



The .second part of the volume deals with the lunar 

 disturbance of gravity, and closes with a pre- 

 diction : — 



" I venture to predict that at some future time 

 practical astronomers will no longer be content to 

 eliminate variations of level merely by taking means 

 of results, but will regard corrections derived from 

 a special instrument as necessary to each astronomical 

 observation." 



GARDEN BOOKS. 



(i) Roses: Their History, Development and Cultiva- 

 tion. By Rev. J. H. Pemberton. Pp. xxiv + 336. 

 (London : Longmans, Green and Co., igo8.) Price 

 los. 6d. net. 



(2) Sir William Temple upon Gardens of Epicurus, 

 with other Seventeenth-Century Garden Essays. 

 Pp. lxxii + 272. (London : Chatto and W'indus, 

 1908.) Pric2 IS. 6d. net. 



(i) "■ I "'HE English literature of the rose ranks higher, 

 J- and is more abundant, than that of any other 

 florist's flower. By general consent the most popular 

 book on the subject was the late Dean Hole's work, 

 entitled "A Book about Roses," which is read with 

 interest even now for the personal reminiscences it 

 contains. "The Rose Garden," by the late William 

 Paul, is a standard work with invaluable illustrations, 

 and "The Book of the Rose," by the Rev. Foster 

 Melliar, of which a new edition was published shortly 

 before the author's death, is an eloquent expression 

 of the views and ideas of an enthusiast in respect to 

 the qualities of the exhibition rose, and the methods 

 of cultivation by which the plants may be induced 

 to produce the most perfect flowers. 



There are many other published works, some 

 newer, others older, than those mentioned, yet such 

 is the interest in the queen of flowers that rose cul- 

 tivators will gladly welcome the latest contribution by 

 (he Rev. J. H. Pemberton. 



Rose-growers visit the exhibitions of the National 

 Kose and other societies, and they are induced to 

 emulate the efforts of the best exhibitors. But if 

 ordinary rose-culture is simple enough to those who 

 are willing to give their time and care to the subject, 

 NO. 2013, VOL. 78] 



it is nevertheless true that the production of perfect 

 blooms such as are capable of winning prizes at an 

 important competitive exhibition is attended with all 

 sorts of difficulties. The less experienced growers, 

 therefore, are willing to learn from those who have 

 already achieved success, and certainly no amateur 

 has been more consistently successful over a long 

 period of years than the author of the book under 

 notice. 



Mr. Pemberton tells us that his father was an 

 ardent rose-grower, and Mr. Pemberton himself com- 

 menced to cultivate roses at the earliest opportunity, 

 being tempted a short time afterwards to enter upon 

 the more adventurous and exciting business of ex- 

 hibiting his blooms at the competitive exhibitions. 



The first portion of the book is devoted to explaining 

 the botanical classification of roses, and to describing 

 some of the more important of the wild species. Some 

 of these are natives of Britain, but the larger number 

 are exotic or foreign. 



The author's request in the first chapter that 

 readers will bear in mind that the rose is not an exotic 

 loses much of its point when we remember that the 

 Hybrid Perpetuals, Teas and Hybrid Teas have been 

 obtained entirely from exotic species ! These earlier 

 chapters may be recommended to the study of 

 hybridists, for they show clearly that very few species 

 have yet been subjected to cross-breeding, and there- 

 fore there are good reasons for the belief that although 

 the present variation in roses is very wide, even 

 greater variation may be expected, and novelties that 

 may establish types altogether distinct from those .at 

 present in cultivation. 



The author has done well to exhort amateur culti- 

 vators to attempt the work of cross-breeding roses for 

 themselves, and notwithstanding that the description 

 given of the processes of fertilisation and fructification 

 is not of scientific exactness, the chapter on raising 

 seedlings will be likely to effect good. 



In the second part of the volume Mr. Pemberton 

 talks straight to the cultivator upon the details of 

 cultivation, carefully and thoroughly explaining the 

 systems of vegetative reproduction, such as budding, 

 grafting, layering, and rooting of cuttings; the 

 tilling and manuring of the soil, planting and pruning. 

 In these pages the author's intimate and practical 

 knowledge of his subject is plainly revealed, and the 

 directions are given so lucidly and yet so tersely that 

 to misunderstand them would appear impossible. 



As the winner of hundreds of friendly battles Mr. 

 Pemberton is able to afford most valuable hints and 

 directions upon the subject of competitive exhibitions, 

 and whilst his enthusiasm for these will be likely to 

 beget also in his readers a desire to engage in the 

 "Wars of the Roses," his helpful counsel will en- 

 courage them to do so with every prospect of obtaining 

 some measure of success. 



We are glad that in this book, written as it is by 

 such an enthusiastic exhibitor, the case for the deco- 

 rative value of roses in the garden is stated so fairly 

 and sympathetically. Not all rose-growers wish to 

 exhibit, but those who do not, equally with those who 



