4i8 



NA TURE 



[August 31, 1882 



the plant under discussion, and this is very useful ; not 

 everyone knows off-hand that " Kafurkachri '' = Hedy- 

 diitm spicatum, or that " l'inde " ' —Stropkantlius Mspidus. 

 Of course these are omissions we do not find in Mr. Kurz's 

 book on the Bamboo, mentioned above ; the volume on 

 the "Eatable Funguses of Great Britain," illustrated by 

 Mr. W. G. Smith, is not referred to, although Mr. Bad- 

 ham's " Esculent Mushrooms" is mentioned; while on 

 the other hand such books as Loudon's " Hortus Britan- 

 nicus " seem hardly to deserve a place. The Index, to 

 which reference has already been made, is all that an 

 index should be, and fully justifies Mr. Jackson's belief 

 that "these entries supply a very fair starting-point for 

 almost every question in vegetable technology." 



Space will not allow us to enter further upon the merits 

 of these Guides. Enough has, however, been said to 

 direct attention to their importance and practical utility, 

 and to encourage the happiest auguries for the success of 

 the magnum opus upon which Mr. Jackson is at present 

 engaged. 



James Britten 



OUR BOOK SHELF 



Talks about Science. By the late Thomas Dunman. 

 (London : Griffith and Farran.) 



Under an unpretending title are here collected a number 

 of lectures that were delivered to popular audiences, 

 chiefly in and about London, by one whose decease, 

 recently, in the early prime of life, has been much de- 

 plored. At the time of his death, Mr. Dunman held a 

 post of tuition in Physiology and Animal Morphology in 

 the Birkbeck Institution, and his labours there and else- 

 where were attended with growing popularity and suc- 

 cess. The biographical sketch by his friend, Mr. Charles 

 Welsh, with which the book opens, tells of the zeal and 

 well-directed energy with which he applied himself to 

 overcoming the obstacles that for some time barred his 

 path to what he considered his true life-work, viz. the 

 teaching of science. These lectures — thirteen in num- 

 ber, deal with a considerable variety of topics, the me- 

 chanism of sensation, the star-lit sky, prehistoric man, 

 volcanoes and coral reefs, atoms and molecules, and so 

 on. The style is terse and lucid, and appears to have 

 been carefully formed on the best models. The happy 

 gift of relieving the strain of which many minds are 

 conscious under mere scientific exposition, by some 

 passing allusion to a familiar human experience, by the 

 homely figure, the apt quotation, the play of imagination 

 and humour, Mr. Dunman seems to have possessed in 

 rich measure. 



The lectures entitled "Two Life Histories" and "How 

 the Earth is Weighed and Measured," may be taken as 

 good examples of abstruse matters expounded without 

 technical language, and made clear for a working-class 

 audience. Mr. Dunman's going down a coal-pit in order 

 to qualify himself more thoroughly for his lecture on 

 " Coal," is typical of much of his work, which in this 

 respect (the " testifying that which he had seen") mani- 

 fested, no doubt, the inspiration of his admired teacher, 

 Huxley. Exception might be taken to a few passages in 

 the lectures, e.%. to the account of ocean temperatures, in 

 " Depths of Ocean " which seems inadequate ; and occa- 

 sionally the author seems to affirm more confidently than 

 the facts warrant. But as a whole the book is a good 

 specimen of sound popularised science, and eminently 

 engaging. As a present to a young artizan with a 

 nascent love of science, it could not fail to be much 

 appreciated. 



LETTERS TO THE EDITOR 



[ The Editor dots not hold himself responsible for opinions expressed 

 by his correspondents. Neither can he undertake to return, 

 or to correspond with the writers of, rejected manuscripts. 

 No notice is taken of anonymous communications. 



[ The Editor urgently requests correspondents to keep their letters 

 as short as possible. The pressure on his space is so great 

 that it is impossible otherwise to ensure the appearance even 

 of communications containing interesting and novel facts. ] 



The " Eira " Arctic Expedition 



I AM confident tbat the anticii ation, contained in your article 

 on Mr. Leigh Smith's expedition (p. 3S7), that he has been able 

 to make some addition to our knowledge of geography, has been 

 realised. 



The object of Mr. Leigh Smith's voyage was a reconnaissance 

 to accumulate evidence respecting the advantages offered by 

 Franz Josef Land as a base of operations for future exploration. 

 He dirt not intend to winter ; but the accident which forced him 

 to do so had the useful result of enabling him to extend his 

 valuable observations over two seasons. The knowledge he thus 

 acquired of the movements of ice, of its character along the 

 shores and in the fiords for sledging purposes, of the prevailing 

 winds and currents, of the amount of animal life to be obtained 

 in the different months, will be very useful. This knowledge 

 will be welcDmed by the geographical student, and will also be 

 of great value to fnture explorers. The loss of natural history 

 collections is to be regretted, but the main object of Arctic 

 exploration is geographical, and that object has been fully 

 secured. 



The crew of the Eira passed through the winter in perfect 

 health. Yet they had no lime juice and, from want of warm 

 clothing, comparatively little exercise during the coldest period. 

 This fact must modify the theories based on the report of the 

 Scurvy Committee. Here we have additional proof that it is 

 fresh meat, and not lime juice, which is the chief preservative 

 of health. 



Another interesting point which the cruise of the Eira w ill 

 throw further light upon, is the direction from which the ice- 

 bearing currents come. In a former letter I called attention to 

 the evidence of Sir Edward Parry on this point, and to the fact 

 that his conclusions had been corroborated by subsequent obser- 

 vation. Mr. Leigh Smith's voyage will furnish additional evi- 

 dence upon this geographical question. As regards the advantages 

 of Franz Josef Land as a base for future discovery, Mr. Leigh 

 Smith has shown that in 1S81 and in 1882 that land could easily 

 be reached ; so that we now have proof that in five consecutive 

 years Franz Josef Land was accessible, that it has suitable bays 

 for winter quarters, that the shore-ice in the fiords offers good 

 sledging surface, and that there is abundance of animal life. 

 Mr. Leigh Smith's voyage will be found to have been most 

 useful to geographical science, and fully to have secured the 

 object of a reconnaissance, for which it was undertaken, 



Clements R. Markham 

 21, Eccleston Square, S.W., August 28 



Markree Magnetic Dip 

 I have made the following determinations of the magnetic 

 dip by aid of one of Dover's excellent Kew -pattern dip-circles 

 (No. 67). As I am observing on a pier in the open air I am not 

 able to always use both needles simultaneously. On August I I 

 observed within a few feet of the wall of the meridian-room. 

 The other observations were made at a distance of over 100 feet 

 from any wall : — 



Dip. 



Needle. 

 No. 2 



Prof. Lloyd determined the magnetic dip at this place forty- 

 seven years ago on 'he same date as follows : — 



1835, August 21 ... 2h. 22m. 72 4' 48". 



