Mar. 26, 1874J 



NATURE 



403 



"... if I examine the nature of this proposition that 'the 

 properties of matter might have been ' other than they are. Does 

 it express an experimentally-ascertained truth ? If so, I invite 

 Prof. Tait to describe the experiments ! " P. G. Tait 



Animal Locomotion 



My former letter on this subject was merely to show that, 

 mechanically, Dr. Pettigrew's view of the forward motion or in- 

 clination of a bird's wing during the down stroke was less .ibsurd 

 than had been supposed, and even seemed necessary to flight. 

 I did not profess to have made accurate observation or experi- 

 ment on the point. I accept, therefore, the observation of the 

 Duke of Argyll as to the vertical motion of the heron's wing ; 

 but as he expressly refers to its great concavity, that would give 

 a vertical down stroke the effect of a somewhat forw'ard stroke 

 of a flatter wing. The proper inference would therefore seem 

 to be, that in birds with less concave wings the stroke is slightly 

 directed forwards. As to the last two paragraphs of his Grace's 

 letter, he will see, if he refers again to mine, that he has quoted 

 words I never used. I impute to Er. Pettigrew the "merit of 

 showing " that the ' ' slight nfrward angle of the mean position of 

 the wing plane is essential to secure horizontal forward motion 

 <;.f a general resultant," &c., and this is exactly what the Duke 

 denies. 



Mr. James Ward's elaborate analysis of the down stroke of a 

 bird's wing simply shows (if correct) that in the position he as- 

 cribes to it (moving downward and backward) it would send the 

 bird horizontally torw-ard. Of course it would. But then what 

 becomes of the bird during the up stroke in an opposite direc- 

 tion? The bird is then falling, and by the downward reaction of 

 all the solid surface of the anterior margin of the wing, and of 

 all the feathers, however obliquely turned, it is driven farther 

 downwards ; and as this takes place l)etween every two down 

 strokes, and approximately during an equal space of time, how 

 is a horizontal average motion to be produced unless the down 

 stroke alone produces, not a horizontal, but a highly-inclined up- 

 ward motion ? Mr. Ward's whole argument appears to me to 

 ignore the great downward reaction, added to gravitation, during 

 every up stroke, which requires that the down stroke should not 

 merely support the bird, but raise it up vertically just as much as 

 during the up stroke it h.as fallen vertically. The matter, how- 

 ever, is no* to be settled by discu-sing theoretically, but by ob- 

 servation and experiment. I simply maintain that the results of 

 Dr. Pettigrew's observations and experiments are not, as sup- 

 posed, inconsistent with mechanical principles ; and nothing in 

 your correspondent's letter induces me to alter that o]iinion. 



Alfred R. Wallace 



'The Newfoundland Cuttle-Fish (Me^aloteuthis hai-Jeyi 

 S. Kent) 



My right being questioned, through an anonymous paragraph 

 in the Clob: of the nth inst., to institute a new generic title for 

 the gigantic Cephalopod encountered off Newfoundland, and of 

 which I communicated an account to the Zoological Society's 

 meeting of March 3, I would briefly reply to my criticiser in 

 these columns. 



In the first place, it is a somewhat anomalous proceeding to 

 raise objections on such a question before details of the grounds 

 upon which it has been deemed advisable to establish such a 

 title have appeared, as in the ordinaiy course of events they will, 

 in the " Proceedings" of tlie Society. In these it will be found 

 that ample reasons are given for the course that has been taken, 

 as also due notice of both Prof. Steerstrup's and Prof. Verrill's 

 researches in a similar direction. Had my assailant placed him- 

 self more thoroughly au couiant with the details of the case, he 

 ,^iuld possibly have held back his emphatic assertion that Prof. 



ni:l had "actually identified the species from Newfoundland 



ill those described by Steenstrup as belonging to his genus 

 - l>i/titeii//iis." This identification in Prof. Vernll's own language 

 is entirely problematical, and must unfortunately remain so, since 

 a beak only, an organ of no value in generic discrimination, has 

 been preserved of the typical species A. dux. Respecting the 

 second form, A. monachus, we ha\e still less knowledj;e, the 

 title being provisionally instituted by Prof. Steenstrup for the re- 

 cep ion of two gigantic Cephalopods cast on the shores of Jut- 

 land in the years 1639 and 1790, and of which popular record 

 alone remains. 



In reference to the " imperfect evidence " asserted by my critic 



to be at my command, I may state that I received accounts of 

 the examples, upon which I have proposed to base my new title 

 of Ale^aloteidhis, direct from America as long ago as in the be- 

 ginning of December last, supplemented by numerous fuller 

 details since. W. Saville-Kent 



Lord Lindsay's Expedition 



The expedition of Lord Lindsay for observation of the Transit 

 of Venus at Mauritius (why will people still call it the Mauritius ?) 

 will afford a good opportunity for re-measuring the liase line of 

 Abbe de la Caille, made in 1753, and which, to the best of my 

 belief, has never been since verified. 



The small conical cairns which mark its extremities should 

 still be found in si/a. I saw one only of them in November 

 1S64, when I had not time to search for the other. The base 

 measured was 1,828 toises in length, and, I imagine, on the 

 meridian. It was on a level plain at the south-west extremity of 

 the island, close under the western slopes of the precipitous and 

 noble" Mome du Brabant," which rises nearly 1,700 feet above 

 the sea-level. By road the distance of this spot from Port Louis 

 must be at least 30 miles, but it is much more easily reached 

 direct by boat ; or, as L>eceniber is a bad time of year for boating 

 outside the reefs, the best route would be from Black River by 

 water inside the isle Beniiier. It is a glorious district, all that 

 part of the island, and contains the finest scenery, including the 

 Chamaral Falls. S. P. Oliver 



Buncrana, near .Londonderry, March 14 



QUE TELE T 



ON February 17 last Jacques-Adolphe-Lambert 

 Quetelet died at Brussels, in the seventy- eighth year 

 of his age, having been born on February 22, 1796, at 

 Ghent. At the early age of 18 he was appointed Pro- 

 fessor of Mathematics in the College of his native town. 

 In July, iSig, the degree of Doctor of Science was con- 

 ferred on him by the University of Ghent, then recently 

 founded by King William. His dissertation on this occasion 

 was so well received that he was shonly thereafter appointed 

 to the Chair of Mathematics at the Royal Athensum of 

 Brussels ; and in February following was elected a 

 member of the Academy of Sciences and Belles- Lettres. 



At this time he applied himself with ardour to the cul- 

 tivation of literature and pure mathematics, thus laying a 

 sure foundation for the world wide fame he afterwards 

 achieved as an exact investigator in many departments of 

 physics, as an original thinker in applying methods of 

 scientific treatment to the discussion of problems pre. 

 viously considered as belonging exclusively to moralists 

 and divines, and as a clear and eloquent expounder of 

 the truths he had demonstrated. The many-sidedness 

 and fertility of his mind may be seen from his scientific 

 memoirs enumerated in the Royal Society's Catalogue of 

 Scientific papers, amounting at the close of 1S63 to 220. 

 He continued to write almost to the last, notwithstanding 

 the mental malady, consisting in loss of memory, with 

 which he was afflicted many years before his death, and it 

 is noteworthy that even to the last his handwriting re- 

 tained much of the rare grace and elegance for which it 

 had been so remarkable. 



The earliest of Ouetelet's published memoirs, begun in 

 1S20, were on geometrical subjects. The non-apprecia- 

 tion of these by the public determined him to devote him- 

 self to physical science and astronomy. On these subjects 

 he lectured publicly with great success. 



In 1S23 he was sent on a mis>ion to Paris with the view 

 of preparing a report on the observatory of that city for 

 the guidance of the Belgian Government in founding a 

 similar observatory at Brussels. After some delay, the 

 observatory was established, with Quetelet as director, 

 and in 1S33 began the long series of observations on 

 astronomy, meteorology, and other physical inciuiries, for 

 which this observatory is so well knowiL The most im- 

 portant of his astronomical observations was the prepara- 



