Nov. 20, 1884] 



NA TURE 



53 



particular excellence in the method of language-teachers. I refer 

 to the practice of making the students acquainted with the works 

 of great writers at the earliest possible period. I should like to see 

 fairly advanced classes of chemical and other students, in schools 

 and elsewhere, reading, with assistance, some of the more suitable 

 memoirs of such men as Davy, Graham, and Faraday. I do not 

 advocate the complete abandonment of text-books, but I should 

 rejoice greatly if their use could be considerably restricted and 

 something better substituted. Has not this neglect of the original 

 writings of great workers by our teachers something to do with 

 the subsequent neglect of research by so many of their pupils? 

 There is of course this practical difficulty in the way of what 

 I propose — that original memoirs are not at present obtain- 

 able in a form in which they can be put in the hands of whole 

 classes of students. If my suggestion should prove acceptable 

 to even a few teachers however, that is a difficulty which could 

 be very easily surmounted. 



(5) When any one proposes to himself a change in his mode 

 of teaching, unless his position is quite exceptional, he always 

 finds himself confronted by one solid difficulty, viz. public 

 examinations of one kind or another. Teachers at first in- 

 spired the examiners. Now they find themselves too often help- 

 less before them. In the face of our various examining Boards 

 individuals are nearly powerless. The time seems to have come 

 when an association of science-teachers for the improvement of 

 science-teaching is a real necessity — something more or less re- 

 sembling the Association for the Improvement of Geometrical 

 Teaching. Such a body would often be invaluable. It could, 

 by the appointment of committees, and perhaps by pecuniary 

 help, promote such experiments as I have suggested in Para- 

 graph (4). In cases such as the recent unfortunate action of 

 the War Office, it might be expected to do good work by re- 

 placing individual by organised action. And it could hardly 

 fail, by bringing teachers and examiners into contact, to do much 

 to make advances in teaching more possible than at present. 



My various remarks on so many points have necessarily been 

 brief and incomplete. I could not, in the form of a letter, go 

 fully into questions of advantage, disadvantage, and difficulty. 

 I shall have amply attained the object I have had in view if I 

 have helped to draw attention to these important matters. 



W. A. Shenstone 



Do Flying-Fish Fly or Not ? 



I have crossed the Atlantic and Indian Oceans many times 

 and at different seasons of the year, but until my last voyage to 

 Calcutta I was unable to answer this question positively. For 

 days together, aided at times by a powerful field-glass, I have 

 endeavoured to establish satisfactorily whether these nimble little 

 fish used their membranous wings after rising above the surface 

 of the sea or not. An old and valued friend, the late Charles 

 Kingsley, on his voyage to the West Indies, so graphically 

 painted in the pages of " At Last," records his opinion in favour 

 of the- wings being employed as a means of propulsion through 

 the air after the fish quit their more natural element, and I 

 certainly inclined to the same belief, although, owing to the 

 "ever-vexed" condition of the Atlantic, I found accurate 

 ill impossible. In the Indian seas the fish appear at 

 rarer intervals, and limit correspondingly the chances of watching 

 their movements. 



On a blazing afternoon in May last, on board the steamer 

 India, some hundred miles off the African coast on the way to 

 Ceylon, I had the first and only opportunity I ever enjoyed of 

 establishing beyond dispute this vexed question, which I am not 

 aware has hitherto been settled. The sea was perfectly calm, 

 covered here and there with a yellow scum which exhaled a 

 fresh unpleasant smell like a beach covered with sea-weed at 

 low water. From the spar-deck above the cabins, which were 

 fitted up in the fore-part of the ship, I could descry at frequent 

 intervals shoals of flying-fish rising and apparently fluttering 

 from 50 to 100 yards before dipping again into the mirror-like 

 surface of the ocean. Along with several of the passengers- 

 some of them provided with field-glasses— I vainly endeavoured 

 to make certain whether the fish did or did not make use of 

 their wings after leaving the water.. Opinions were divided, 

 for, owing to the rapid motion of the fish, it was impossible to 

 keep any one of them long enough in the field of vision. It 

 occurred to some of us at length to look over the bows of the 

 steamer, and there we saw a sight not soon to be forgotten. 

 The flying-fish appeared frequently shooting upwards in large 



numbers from the blue glassy depths directly beneath us, as the 

 shoals were disturbed by the vessel's cutwater, and their every 

 movement plainly discernible while under water and from the 

 moment they rose "winnowing the waving element" with 

 expanded wings aid tail, bent on escaping the pursuing craft, 

 until they dipped again into the sea for shelter or to obtain fresh 

 impetus for continued flight. I satisfied myself, and so did my 

 fellow-watchers, that after a certain number of strokes with 

 wings and tail — from twenty to thirty, varying with the dimen- 

 sions of the fish — which we repeatedly counted, as they left cor- 

 responding impressions on the oily surface of the water, these 

 appendages were not employed to accelerate, but merely to 

 sustain, the flight while the fish remained in the air. The 

 curved impressions left by the wings on the water appeared, as 

 nearly as I could judge, from twelve to eighteen inches apart on 

 either side of the fishes' course until clear of the water. The 

 tail left no perceptible imprint, but could be clearly seen waving 

 from side to side, adding doubtless considerably to the impulse. 

 After rising out of the water the wings and tail remained ridged, 

 but in some instances were slightly twisted to preserve the 

 equilibrium. Occasionally a fish appeared to lose its balance in 

 the hurry of escape, and toppled over in a ridiculous fashion. 



The yellow scum also attracted attention, tinging the ripple at 

 the bows a deep orange. I had some of it brought on board, 

 and a fellow-passenger of an entomological turn placed some 

 under a powerful microscope, but failed to determine the species 

 to which it belonged. Ten years ago, near the same place, I 

 observed the water assume a dirty yellow tinge, as though it had 

 suddenly shoaled, while the same unpleasant smell was per- 

 ceptible. The discoloration and smell I found to be due to the 

 presence of vast quantities of animalcula, about a quarter of an 

 inch long, semi-transparent, jointed like a cane, and about the 

 thickness of a small needle. Robert W. S. Mitchell 



8, Garden Reach, Calcutta 



Earthquake Measurements 

 I regret that Prof. Ewing should take so much to heart my 

 criticisms of his results of earthquake registration. I think that 

 if we can get a single movement instead of a double one we gain 

 much by halving the errors of douhle registration, extra friction, 

 complexity of calculation, &c, all causes that tend to increase 

 the imperfection of the results. 



Neither did I intend to disparage seismological investigations 

 on the plain of Yedo, but it does seem to me that the first 

 thorough study, such as Prof. Ewing and others have initiated, 

 should be in a locality where the minimum of disturbing influ- 

 ences would be able to complicate the results. In fact, we 

 should expect much more progress in arithmetic in a child which 

 commences by learning to count than in another that is imme- 

 diately put to study fractions. I should never suggest that one 

 earth-shaken locality should be continuously studied more than 

 another when once we have decided upon the most serviceable 

 and accurate registering apparatus. 



Now as a resident in a country continuously shaken by earth- 

 quakes, many of which are disastrous, and where investigators 

 are few and far between, we want instruments that give the 

 least complicated tracings possible if we are to find observers 

 amongst inhabitants of the Italian provincial towns. The same 

 thing holds good to a variable extent in other countries. 



Again, hardly any one would accuse me of claiming entire 

 originality for the principle in the apparatus described. For 

 example, every one knows that the pendulum has been used as 

 a seismograph for centuries even. All that I claim is a com- 

 bination of different forms of actuating and registering appara- 

 tus, with a few novel introductions, for it is practically impos- 

 sible to invent, in the true sense of the word, a new seismograph 

 any more than a new locomotive. 



Perhaps, in my critic's opinion, we have reached perfection in 

 seismographic instruments, which it appears is not shared by 

 many workers, as the continual new suggestions and modifications 

 indicate, as does also the fact that throughout all the observing- 

 stations so far instituted it is rare to find two provided with 

 similar instruments. 



In regard to Prof. Swing's last paragraph, perhaps experience 

 will determine whether my suggestions do really lie outside the 

 sphere of practical seismology. 



In conclusion I shall be happy to hear suggestions for any 

 improvements from others, for in my own humble opinion we do 

 not yet possess a single seismograph that reaches near to perfec- 



