78 



NATURE 



[November 23, 189^ 



to render the stratifiefl appearance of the rock very marked at 

 comparatively great distances from them. 



There is in many cases a crack marking the junction of con- 

 tiguous layers. 



As an illustration of these "composite " dykes, I append a 

 diagrammaiic sketch representing a section of the coast about 

 200 or 300 yards south of the Cligga promontory, which is very 

 difficult of approach. 



A has all the appearance of a bed of sandstone, the strata 

 curved, owing to the intrusion of the dyke B (granitic) ; C is an 



// 



'3^ 



Fig. 



old tin burrow. As a matter of fact, each is a granitic dyke, A 

 finer grained than B, and very like sandstone in all petrological 

 features. 



The reinarkal)le fact is the apparent stratification of the beds 

 A, which are rrally bands of several dykes — a continuation of 

 those figured a' p. 164 in De La Beche's book. He does not 

 seem to have observed this instance, or at any rate does not 

 mention it ; his figure is from the cliff immediately in contact 

 with the Clig>ja promontory, and north of that I have figured. 



Further instances of this very interesting kind of composite 

 dyke would hel,' in many cases to unravel the seeming com- 

 plexity of such geological features as those I have lojched upon 

 in Cornwall. Henry E. Ede. 



45 Walker Terrace, Gateshead-on-Tyne, October 4. 



Weismannism. 



I NEVER answer reviews, save in so far as they may be mis- 

 leading on matters of (act. As this is the case with "P. C. M.'s" 

 notice of my "Examination of Weismannism" (Nature, 

 November 16), I should like to say a few words touching the 

 more important of such matters. 



It setms that in seeking to do justice to all sides in the heredity 

 question, I have been too careless in expressing my own view. 

 At all events, any one reading the review must gather from it 

 that I am a Lamarckian engaged in fighting the theories of Prof. 

 Weismarin. in the book, however, it is stated that I have been 

 an adherent of the theory of Stirji ever since it was published 

 by Mr. G:dton in 1875. It is also staled that this theory is, 

 in my opinion, identical, as regards all main principles, with that 

 of Gtrmplasm in the present phase of its numerous metamor- 

 phoses. Therefore, far from fighting the Weismannian theory 

 of heredity, I see in all its main features, as it now stands, a 

 " re-pul)lication" of the one which I have held for close upon 

 twenty years. 



It is further stated that the only points of much secondary 

 importance wherein I can perceive the two theories to differ are, 

 / . that while Gallon coifined him.self to publishing a theory 

 Heredity, Wei mann proceeded to rear upon this basis {i.e., 

 ilic hypothesis (.f "continuity") a further and elaborate theory 

 of otgmic evolution ; and, (/;), that Weismann has not gone so 

 far a- Gabon did in expressly recognising the possibility of an 

 occasioT'al transmission of acquired characters, in faint though 

 presumably accumulative degrees. As regards these two points 

 of difference, 1 have endeavoured to show, [a), that Weismann 

 has now himself withdrawn nearly all his previous generali.'a- 

 tions with regard to organic evolution, while largely modifying 

 his the..ry of heredity ; and, [b), that he has only to expand cer- 

 tain hints \\hich he has already given— and which, if expanded, 

 would eiitail much less modification of his original system than 

 those which he has now made in other parts thereof— m order as 



NO. 1256, VOL. 49] 



fully to recognise as Galton did the possibly occasional trans- 

 mission of acquired characters. 



Hence, such opposition as I have found any reason to express 

 with regard to Weismann's system in the late-t phase of its 

 development arises, almost exclusively, aga nst the inordinately 

 speculative character of his method. The history of science 

 furnishes no approach to such a disproportion between deduction 

 and induction. 



Thus it seems to me that any wriier on Weismannism who 

 aims at impartiality must fail in his aim, if he does not give due 

 prominence to this the most distinctive feature of Weismann's 

 method. And, unless the reviewer is prepared to defend such 

 a method as scientific, he has no reason to quarrel with what 

 he calls my "hard words," since they all have reference to 

 it, and are statements, not of opinions, but of facts. 



On the other hand, I have endeavoured by "soft words" 

 to fully rec ignise the great merit of Wei>mann's work in con- 

 sti'uting the heredity questi >n one of world- Aide interest. And 

 any bias that I may have with regnrd to this question is as- 

 suredly on the side of " continuiiy," although 1 cannot hold 

 that the subordinate question is closed — i.e., as to whether sucli 

 continuity can never, under any circumstances or in any degrees, 

 be interrupted. GejRGE J. Romanes. 



Hyeres, November 20. 



Correlation of Solar and Magnetic Phenomena. 



Mr. Ei.lis, in his letter (Nature, November 9), has dis- 

 cussed the coincidence between Carrington's o!)servation of a 

 solar outburst in 1859 and the magnetic movements observed at 

 Kew and Greenwich. He comes to the conclusion 'hat the dis- 

 turbance of the magnets corresponding to this outburst was 

 small, and that, although many greater magnetic movements 

 have occurred since, no corresponding minifesiation has been 

 seen, although the sun has been so closely watched. 



He appears to have overlooked an observation mide at Sher- 

 man, by Prof. Young, which shows a very striking series of 

 coincidences, and which is described in his work, " fhe Sun'" 

 (p. 156), in the following words: — "On Au^ju t 3, 1872, the 

 chromosphere in the neighbourhood of a sun-«|)Ot, which was 

 just coming into view around the edge of the sun, was greatly 

 disturbed on several occasions during the forenoon. Jets of 

 luminous matter of intense brilliance were projected, and the 

 dark lines of the spectrum were reversed by hundreds for a few 

 minutes at a time. There were three especially notable 

 parrxysms at 8.45, 10.30, and II.50 a.m., local time. At 

 dinner the photographer of the party, who \n as making our 

 magnetic observations, told me, before knoA'ing anything about 

 what I had been observing, that he had been obliged to give up 

 work, his magnet having suung clear off the scale. Two days 

 later the spot had come round the edge of the limb. On the 

 mornin.jof August 5, I began ol seivations at 6.40, and for about 

 an hour witnessed some of the most rematkal)le phenomena I 

 have ever seen. The hydrogen lines, wiih many others, were 

 brilliantly reversed in the spectrum of the nucleus, and at one 

 point in the penumbra the C line sent out what looked like a 

 blowpipe jet, projecting toward the up|)er en I of the spectrum, 

 and indicating a motion along the line of sight of ab )ut 120 

 miles per second. The motion would die oai and be renewed 



again at intervals of a minute or two The disturbance 



ceased before eight o'clock, and was not renewed thai forenoon. 

 On writing to Englarid, I received from Greenwich and Stony- 

 hurst, through the kindness of Sir G. B. Airy and Rev. S. J. 

 Perry, copies of the photographic magnetic records for those 



two days On August 3, which was a day of general 



magnetic disturbance, the paroxysms I noticed at Sherman were 

 accompanied by peculiar twitches of the magnet in England. 

 Again, August 5 "■'^-s a quiet day, magnetically speaking, but 

 ju-t during that hour, when the sun-spot was acive, the magnet 

 shivered and trembled. So far as app' ars, too, the magnetic 

 action of i he sun was instantaneous. After making allowance 

 for longitude, the magnetic dis'uibance in England was strictly 

 simulianeous, so far as can.be judged, with the spectroscopic 

 disturb ince seen on the Rocky Mountains." 



These observations of Prof. Young's seem to invali late Mr. 

 Ellis's statement that " no second occuirence similar to that of 

 1S59 has come to light," and that although there undoubtedly 

 exists a relation between suii-spo's and magnetism, "it has not 

 yet been found possible to trace direct correspondence in details. 



Cambridge, November 12. A. R. IliNKS. 



