Movements 

 Music 



SCIENTIFIC SIDE-LIGHTS 



468 



do with the actual carrying out of the effect. 

 And this is proved by the circumstance that 

 these acts can be performed with complete 

 mental abstraction; and, more than this, that 

 the endeavor to carry them out entirely 

 by the exercise of the will is not only not 

 beneficial, but positively interferes with their 

 harmonious and perfect performance. Any 

 one may convince himself of this fact by 

 trying to take each step as a voluntary act 

 in walking down-stairs, or to form each let- 

 ter or word in writing by a distinct exercise 

 of the will. BAKER Handbook of Physi- 

 ology, vol. ii, ch. 18, p. 102. ( W. W., 1885.) , 



2292. MOVEMENTS OF EARTH'S 



CRUST "Term Firma" a Delusion. The 

 folds and corrugations of the strata and 

 the numerous dislocations by which rocks 

 of all kinds are traversed clearly demon- 

 strate that movements of the solid crust 

 have taken place. Such crustal disturbances 

 are probably in chief measure due to the 

 fact that the earth is a cooling body. As 

 the solid crust sinks down upon the cooling 

 and contracting nucleus, it must occupy less 

 superficial space. Hence its rocky frame- 

 work becomes subjected to enormous tan- 

 gential squeezing and compression, to which 

 it yields by bending and folding, by frac- 

 ture and displacement. GEIKIE Earth 

 Sculpture, ch. 1, p. 13. (G. P. P., 1898.) 



2293. MOVEMENTS OF FLYING-FISH 



A True Flight Fear Drives the Fish into 

 Alien Element of Air. I have had frequent 

 occasions to observe the flying-fishes atten- 

 tively. I am confident not only that they 

 change the direction of their flight, but that 

 they raise or lower their line of movement 

 repeatedly, without returning to the water. 

 I avoid the word " falling " designedly, for 

 all the acts of these fishes during their flight 

 seem to me completely voluntary. They 

 raise themselves from the surface of the 

 v.ater by rapidly repeated blows with the 

 tail, and more than once have I seen them 

 descend again to the surface of the water in 

 order to repeat this movement; thus renew- 

 ing the impulse .and enabling themselves to 

 continue for a longer time their passage 

 through the air. Their changes of direction, 

 either to the right and left or in rising and 

 descending, are not due to the beating of the 

 wings, that is to say, of the great pectoral 

 fins, but simply to an inflection of the whole 

 surface, in one or the other direction, by the 

 contraction of the muscles controlling the 

 action of the fin-rays, their pressure against 

 the air determining the movement. The 

 flying-fish is in fact a living shuttlecock, 

 capable of directing its own course by the 

 bending of its large fins. It probably main- 

 tains itself in the air until the necessity of 

 breathing compels it to return to the water. 

 The motive of its flight* seems to me to be 

 fear; for it is always in the immediate 

 neighborhood and in front of the vessel that 

 they are seen to rise; or perhaps at a dis- 



tance when they are pursued by some large 

 fish. AGASSIZ Journey in Brazil, ch. 2, 

 app., p. 522. (H. M. & Co., 1896.) 



2294. MOVEMENTS OF MUSCLES 

 ASSIGNED TO CENTERS IN THE BRAIN 



Dr. R. W. Amidon in 1880 [succeeded in 

 localizing] the heat produced [in the brain] 

 by voluntary muscular contractions. Apply- 

 ing a number of delicate surface-thermom- 

 eters simultaneously against the scalp, he 

 found that when different muscles of the 

 body were made to contract vigorously for 

 ten minutes or more, different regions of the 

 scalp rose in temperature, that the regions 

 were well localized, and that the rise of tem- 

 perature was often considerably over a 

 Fahrenheit degree. As a result of his inves- 

 tigations he gives a diagram in which num- 

 bered regions represent the centers of high- 

 est temperature for the various special 

 movements which were investigated. To a 

 large extent they correspond to the centers, 

 for the same movements assigned by Ferrier 

 and others on other grounds; only they 

 cover more of the skull. JAMES Psychology? 

 vol. i, ch. 3, p. 100. (H. H. & Co., 1899.) 



2295. MOVEMENTS WITH REFER- 

 ENCE TO ENDS A Faculty of Plants as Well 

 as of Animals Venus's Fly-trap Climbing 

 Tendril. The faculty of making movements 

 in reference to ends, affirmed of animals, 

 was long denied to plants. ... To 

 show the breaking-down of the distinction, 

 it would suffice to contrast the rooted fixity 

 and vegetative growth of very many lower 

 animals with the free locomotion of most 

 microscopic aquatic plants and of the germs 

 of those not microscopic. Is there not an 

 independent movement, in response to an 

 external impression, and in reference to an 

 end, when the two sides of the trap of 

 Dioncea [or Venus's fly-trap] suddenly en- 

 close an alighted fly, cross their fringe of 

 marginal bristles over the only avenue of 

 escape, remain quiescent in this position 

 long enough to give a small fly full oppor- 

 tunity to crawl out, soon open if this hap- 

 pens, but after due interval shut down 

 firmly upon one of greater size which cannot 

 get out, then pour out digestive juices, and 

 in due time reabsorb the whole? So, ... 

 when a free revolving tendril avoids wind- 

 ing up itself uselessly around the stem it be- 

 longs to ... by changing from the 

 horizontal to the vertical position until it 

 passes by it, and then rapidly resumes its 

 horizontal sweep, to result in reaching a 

 distant support is it possible to think that 

 these are not movements in reference to 

 ends? ASA GRAY Natural Science and Re- 

 ligion, lect. 1, p. 22. (S., 1891.) 



2296. MULTIPLICATION BY DIVISION 

 AMONG BACTERIA Division, or fission, is 

 the commonest method of reproduction [of 

 bacteria]. It occurs transversely. A small 

 indentation occurs in the capsule, which ap- 

 pears to make its way slowly through the 

 whole body of the bacillus or micrococcus 



