384 



NATURE 



[Fed. 27, 1879 



Seco7tda Contribtizione morfolo^ia e sistematica del 



Selachi. Del Prof. Pietro Pavesi. (Genoa, 1878.) 

 In 1874 Prof. Pavesi, of Pavia, described in the Antiali 

 del Museo Civico of Genoa a shark which had been 

 captured at Lerici, in the Gulf of Spezzia, in 187 1. It 

 belonged to the genus Selache, but, from a peculiarity in 

 the conformation of the rostrum, Pavesi considered it 

 to be a distinct species from the great basking shark, 

 Selache maxima, and named it Selache rostrata. The 

 specific difference of this specimen has, however, been 

 called in question by Canestrini, Steenstrup, and other 

 ichthyologists, who were inclined to regard it as a mon- 

 strous form of the Selache maxima. In June, 1877, 

 a male shark, also belonging to the genus Selache, 

 was caught in the harbour of Vado, near Savona, 

 and, being examined by Prof. Pavesi, forms the sub- 

 ject of this second communication to the Amiali 

 del Museo Civico, vol. xii. Its length was between 

 ten and eleven feet. It had been eviscerated before 

 coming into his possession, so that the memoir does 

 not give an account of the abdominal viscera, but the 

 external characters, the skeleton, the pectinated appen- 

 dages, the brain and cranial nerves, and the vascular 

 system, are described. The shark from Vado is almost 

 identical, says the author, with that previously caught at 

 Lerici. He then carefully reconsiders the systematic 

 position of these specimens. He is strongly of opinion 

 that the view that the specimen originally described was 

 a monstrous form of Selache maxima is quite untenable. 

 But his examination of this second specimen has con- 

 vinced him that these sharks can no longer be regarded 

 as a distinct species, and that they are young examples of 

 the great basking shark, Selache maxima. The memoir 

 is illustrated by a lithographic plate and by twenty-seven 

 woodcuts. 



Das Leben. Nattirwissenschaftliche Entivickelnng des 

 organischen Seelen- und Geisteslebens. Von Philipp 

 Spiller. (Berlin : Stuhr'sche Buchhandlung, 1878.) 

 This work may be said to be but an enlarged reproduc- 

 tion of a division of an earlier and more important work : 

 " Die Urkraft des Weltalls nach ihrem Wesen und Wirken 

 auf alien Naturgebieten," by the same author. Prof. 

 Spiller, whose death it was our painful duty to announce 

 last week, is the originator and founder of a philosophical 

 theor>' on the first cause of all things. According to his 

 view the world-ether is the architect of the universe as 

 well as the fundamental cause of gravitation. In his 

 works, particularly in the one just mentioned, the learned 

 professor treats this world-ether theory in a most masterly 

 manner, a.nd whatever view we may take as to the correct- 

 ness of his views — a question which we certainly do not 

 wish to decide — it is only justice to point out that his 

 explanations and definitions are all written in such a 

 spirit of firm conviction of the truth of his theory, that 

 an attentive reader cannot refuse his admiration and 

 respect. 



LETTERS TO THE EDITOR 



[ The Editor does not held 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 com- 

 munications containing interesting and novel facts.\ 



Leibnitz's Mathematics 



I UNDERSTOOD Dr. Ingleby to say that he was prepared to 

 make good his assertions, and to respond to Mr. Nelson's "call" 

 as soon as I retracted, or justified, my former statement. 



In 1871 Dr. Ingleby said it was exactly twenty years since the 

 last vestige of presimiption against the fair fame of Leibnitz was 

 "obliterated." 



Dr. Ingleby is evidently unacquainted with the work of Dr. 



Sloman (Leipzig, 1858 ; in English, Macmillan, i860), else he 

 would not have spoken of the "last vestige of presumption." 



Kant's opinion of Leibnitz, which is far more favourable than 

 that of Dr. Sloman, compares him to chemists "who gave 

 themselves out to be possessed of secrets, when they had really 

 nothing but a persuasion and a conviction of their capacity for 

 acquiring such." This verdict, from a true metaphysician, ought . 

 to have much weight with Dr. Ingleby. P. G. Tait 



Guthrie's "Physics" 



Some weeks ago (p. 311) you published in Nature a revievf 

 by Prof. Maxwell of a little book of mine on Practical Physics. 

 It is not my intention to complain in any way of the review, 

 partly because it would be a profitless trespass on your space, but 

 mainly because, while the tone is unfavourable, the instances 

 adduced by the reviewer go a long way to confute his own state- 

 ments in all • cases where there is any connection between the 

 two. 



Some well-meaning friend has composed and sent me a copy 

 of the inclosed. There appear to be various opinions as to the 

 authorship. It has even been suggested that Prof. Maxwell, with 

 that sense of humour for which he is so esteemed, and with a 

 pardonable love of mystification, is himself the author, 



February 24 Fredk. Guthrie 



Remonstrance to a Respecteb Daddie Anent His Loss 



OF Temper 

 Suggested by Prof. Clerk Maxwell's review of Guthrie's 

 "Physics" 

 Worry, through duties Academic, 



It might ha'e been 

 That made ye write your last polemic 

 Sae unco keen : 



Or intellectual indigestion 



O' mental meat. 

 Striving in vain to solve some question 



Fro' " Maxwell's Heat." 



Mayhap that mighty brain, in gliding 



Fro' space tae space. 

 Met wi' anither, an' collidin'. 



Not face tae face. 



But rather crookedly, in fallin' 



Wi' gentle list, 

 Gat what there is nae help fro' callin' 



An ugly twist. 



If 'twas your "demon" led ye blindly. 



Ye should na thank him, 

 But gripe him by the lug and kindly 



But soundly spank him. 



Sae, stem but patronising daddie ! 



Don't ta'e 't amiss. 

 If a puir castigated laddie 



Observes just this : — 



Ye 've gat a braw new Lab'ratory 



Wi' a' the gears. 

 Fro' which, the waild is unco sorry, 



'Maist naught appears. 



A weel-bred dog, yoursel' must feel, 



Should seldom bark. 

 Just put your fore paws tae the wheel. 



An' do some Wark. f^ 



Unscientific Art 



In Punches series of cartoons, "the man at the wheel" turns 

 up now and again. The most recent example is that of 

 date February 22 : John Bull and Punch are strenuously holding 

 a steering-wheel between them, in a tempestuous scene. I have a 

 second example before me in the series of cartoons of Beaconsfield 

 recently-issued. No. 61 : Disraeli has one hand on a steering-wheel, 

 while the other holds a pistol directed to the powder magazine 

 below ; and he threatens to blow up the ship if Gladstone and 

 Bright (climbing over the bulwarks behind) step on board. 

 Other cases will be remembered. Now (neglecting here the 

 political meaning of the pictures) these steering-wheels are won- 

 derful productions, and how they serve for steering is a mystery. 

 The wonder, remarked on by St. James, of "a very small 



