October 13, 1904] 



NA TURE 



577 



LETTERS TO THE EDITOR. 



\The Editor does 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 intended for this or any other part of Nature. 

 No notice is taken of anonymous communications.] 



The Forest-pig of Central Africa. 



It may interest many of your readers to know that the 

 " forest-pig " heard of, at the same time as the okapi, by 

 Sir Henry Stanley, and later on by Sir Harry Johnston, has 

 at last been obtained and presented to the National Museum 

 by Mr. R. Meinertzhagen. 



This gentleman lirst had news of it from the natives of 

 Mount Kenya, and took great pains to secure a specimen, 

 but only succeeded in obtaining pieces of skin, from which 

 no idea of its affinities could be gathered. At last, however, 

 in the Nandi Forest, near the Victoria Xyanza, at an altitude 

 of 7000 feet, he received two skulls, one quite perfect, and 

 -ome further portions of skin. 



These trophies show that the animal represents a most 

 nteresting new genus connecting the aberrant wart-hog 

 l'hacocha:rus) with the more ordinary Suid<-E, such as Sus 

 ind Potamochsrus. It agrees with the first named in the 

 lumber of its incisors, and shows a tendency towards it in 

 ihe development of the canines and the structure of the 

 Tiiolars. On the other hand, in the general proportions of 

 the skull it is more like Sus. 



-Altogether, if it cannot be called absolutely ancestral to 

 rhacocha;rus, it must at least be looked upon as represent- 

 ing an. early stage in the specialisation of that most remark- 

 able type. 



The animal itself is about as large as a wart-hog, and is 

 well covered with long coarse black hair. 



It is proposed to be called Hylochocrus meinertshageni, 

 and I hope to give a full description of it at an early 

 meeting of the Zoological Society. 



Oldfield Thom.as. 



British Museum (Natural History), October 7. 



Appeal for Cooperation in Magnetic and Allied Obser- 

 vations during the Total Solar Eclipse of August 

 29 30, 1905. 



Those who are in a position to take part in the above 

 cooperative work are earnestly requested to make the 

 necessary preparations and to put themselves in com- 

 munication with the undersigned. 



.As this will be the best opportunity for some time to 

 come to test and observe further the magnetic and electric 

 phenomena which have been found to occur in connection 

 with total solar eclipses, and as these phenomena are 

 destined to play an important rule in the theory of those 

 variations of the earth's magnetism and electricity ascribed 

 to outside forces, it is very much hoped that all countries 

 through which or near which Ihe belt of totality passes 

 will organise and send in the field observing parties. 



Owing to the minuteness of the expected magnetic effect, 

 the burden of proof as to its association with the eclipse 

 will largely consist, as in the two previous eclipses, in the 

 connection of the times of the magnetic effects with the 

 times of passage of the shadow cone at the various stations. 

 The observing parties, therefore, should be distributed at 

 intervals along as much of the entire belt as possible. 



The above is merely a preliminary notification of the work 

 proposed. Fuller details and suggested directions to be 

 followed will be given later. L. .\. B.aler. 



Department of Terrestrial Magnetism, The Ontario, 

 Washington, D.C., U.S.A. 



Instinct and Reason in Dogs. 



The following statements may be of interest to those of 

 your readers who have at times discussed the question of 

 instinct and reason in dogs. 



.\ friend of mine was in a strange town, having with him 

 an Irish terrier. Finding it necessary to fasten the dog up 

 outside a house, he did so by tying it with a piece of cord. 

 On coming out of the house he was just in time to see his 



NO. 1824, VOL. 70] 



own dog being led away by a strange dog holding the cord 

 in his mouth, having bitten it through. My friend often 

 takes this same terrier, together with a fox terrier, out with 

 him when calling. He ties the fox terrier by a cord to the 

 scraper ; as often as not the Irish terrier bites through the 

 cord and frees his friend. 



Mv own fox terrier seldom if ever goes to the stables, 

 and whilst I am absent from home for a few days remains 

 in his usual place ; but almost invariably on the day when 

 I am expected back he pays frequent visits to the stable, and 

 is anxious to go with the carriage if he sees it being got 

 ready ; at all other times he is not willing to go with the 

 carriage unless I am in it. On the two last occasions when 

 I was expected home the dog acted as previously, but, in 

 addition, jumped into the carriage as soon as it was brought 

 out of the coach-house, a thing which he has never done 

 before. E. W . P. 



October 8. 



Misuse of Words and Phrases. 



As a constant reader of Nature and of papers read before 

 scientific societies, I have been struck by what seems to 

 me an inaccurate use of language by English men of science 

 which is rarely chargeable upon Americans — which is, at 

 any rale, at' variance with American usage. I will 

 illustrate with the following examples ; — 



One star is five light-years distant ; another is twenty-five 

 light-years distant. The English astronomer will say that 

 the second is five times farther away than the first. 



.\ mass of aluminium weighs one pound ; a mass of lead 

 of equal size weighs something more than four pounds. 

 The English physicist will say that aluminium i' more 

 than four times lighter than lead. 



Both expressions seem to me incorrect and unworthy of 

 a man of science who endeavours to e.xpress himself 

 accurately. In the one case he should say that one star is 

 five times as far away as the other. In the other case the 

 whole expression is vicious. Weight, heaviness, is an 

 attribute of matter ; lightness is absence, or deficiency, of 

 weight. To say that one article is a certain number of 

 times lighter than another is like saying of two vessels 

 unequally exhausted of air that one is four times emptier 

 than another. 



It is good English— is it not?— to say that one article 

 is twice as heavy as another. If it is twice heavier, it is 

 three times as heavy. 



I submit this criticism of an Anglicism as an offset to 

 some one of many criticisms of Americanisms. 



Boston, U.S.A. E- S. 



N.iTUR.iL HISTORY ESSAYS.-" 



ON the whole, Mr. Renshaw appears to have been 

 well advised in re-issuing in book form the 

 sixteen articles and lectures which constitute the 

 volume before us, since several of thein contain much 

 important information with regard to species now 

 verging on extinction, or which have been already 

 exterminated, while all are eminently readable and full 

 of interest. \\'hether the author has quite done himself 

 justice in the title he has chosen for his work may 

 be open to question, seeing that all the articles relate 

 to a single subject, namely, the mammals of Africa. 

 Undoubtedly the most generally interesting and im- 

 portant articles of the series are the two dealing with 

 the quagga and the blaauwbok, next to which may 

 perhaps be ranked those on the white rhinoceros, the 

 pigmy hippopotamus, and the giraffe. The book is 

 abundantly illustrated with reproductions from photo- 

 graphs, many of which, like the one here shown, are 

 excellent examples of animal photography. 



While there is much to commend in the work before 

 us, there are also matters with which to find fault. In 

 the first place, the author has not revised his articles 



1 "Natural History Essays." By G. Renshaw. Pp. .viv-f2i8; illus- 

 trated. (London and Manchester: Sherratt and Hughes, 1904.) Price 6s. 



