July 28, 1887] 



NATURE 



297 



every city system of schools, and quotes Germany's 

 example, followed by Austria after Sadovva. Credit is 

 given also to the Germans for leading the way in venti- 

 lating school-rooms scientifically. In 1858 Pettenkofer's 

 method of testing the impurity of the air in a room came 

 into use, and a description is here given of a different 

 simple apparatus for the same purpose. The conclusion 

 is drawn that organic matter in "bad air" is more 

 frequently the dangerous part of it than superabundant 

 carbonic acid. England, while at the higher schools 

 formally ignoring this branch of education, never- 

 theless really recognises it in the games which make 

 themselves of so much importance at the Universities 

 and the great schools that feed them. Physical training 

 was despised and repressed by the monks of old, who 

 founded these schools, and taught that the body was at 

 enmity with the soul, and that the more the former was 

 weakened the more the latter was strengthened and puri- 

 fied ; and if with Mr. Galton we regret that all the soften- 

 ing elements of human nature were eliminated by 

 monastic celibacy, we may also console ourselves that, 

 but for it, many injured constitutions must have been 

 handed down as the result of such tenets. Schoolmasters 

 now know that the difficulties of teaching are immensely 

 increased by any physical disorder, and that an absolute 

 incapacity to learn follows some bodily ailments. Im- 

 perceptibly increasing from the sleepiness which follows 

 upon a good dinner comes the dulness caused by the bad 

 air of ill-ventilated rooms. There is a long and full paper 

 on this latter subject prepared for independent publication 

 jjy the Bureau of Education, of great value but too general 

 in its teaching to be epitomised here. 



Another cause of what to thoughtless teachers seems 

 irritating stupidity is partial deafness. Interesting ob- 

 servations upon the varieties of this infirmity among 

 school children have been made by Dr. Sexton, of New 

 York. Careful estimates show that only 5 per cent, of 

 the entire population of the United States have normal 

 hearing. Ten per cent, of pupils have such defective 

 hearing as to make special placing and such like care for 

 them in schools necessary. If a teacher has not made 

 himself fully acquainted with the amount of this deafness, 

 a very slightly deaf pupil will either be liable to be sent 

 to the deaf-and-dumb school, or he will leave the ordinary 

 school in disgust at the teachers harsh and unfair repri- 

 mands. Prof. Graham Bell's audiometer is found to 

 answer well in the work of classifying defective hearers. 

 On behalf of the deaf-mute school Mr. Dobyns boasted 

 that theirs was the only universal language : when he 

 met an educated deaf-mute not only from America but 

 from France, Germany, England, or Japan, he could 

 hold communication with him. 



Krom an examination of about forty thousand cases, a 



ommittee on the subject draws the important conclusion 

 that, while very few pupils indeed are short-sighted when 

 they first enter school, " the number afflicted, and the 

 degree or intensity of the disease, gradually but surely 

 increase through the entire school life, from class to class, 

 from year to year, until, when the Colleges and Univer- 

 sities are reached, in many cases more than half the 

 students are near-sighted." This Committee strongly 

 recommends increased use of the black-board and less use 

 ol books. This practice has been found to reduce the 

 lount of myopia to one-half. A Report of a second 



'.mmittee on the causes of it recommends that the 

 head should not be bent forward too much over a desk. 

 Near-sightedness has increased in Alsace since German 

 letters have been used there. There is a special danger 

 of its being brought on at about fifteen years old, the age 

 of puberty. 



While these deficiencies are to be found in so large a 

 proportion of children, however, Mr. Jepsen, teacher of 

 music in New Haven, limits the number of children who 

 have really what is called " no ear " for music to less 



than 4 per cent., and he urges that it may profitably be 

 taught in a thoroughly scientific way to be familiarly 

 read. The Commissioner has felt the importance 

 of this matter so much that through the co-opera- 

 tion of a Music Teachers' Association the heavily 

 burdened Bureau has been already able to draw 

 up and issue a Circular of Information on the study of 

 music in public schools. It is remarked that singing 

 seems to be despised as a school pursuit in the United 

 States, and to be less popular and more neglected than in 

 England. It is taught that mental culture comes chiefly 

 through the eye ; moral culture through the ear and 

 voice. Sounds can be taught to children much more 

 easily than numbers. To read music, again, is as great a 

 superiority over singing it by ear as being able to read is 

 better than having learnt a few pieces by heart. 



Bearing upon the same question of classifying children 

 according to their powers is a short paper read by Mr, 

 E. Chadwick, of educational celebrity in England, who 

 urges the economy of dividing the bright children from 

 the dull, so as to educate them in less time — a most 

 desirable arrangement for all parties, where it is 

 practicable. 



Two papers, one of them also by Mr. Chadwick, take 

 up the subject of rewards and punishments. Mr. Chadwick 

 protests against the use of the stick, while Prof. Barbour urges 

 first the needlessness, and then the danger, of giving prizes, 

 which may breed a sordid character, supply unworthy and 

 therefore unstable motives. They are,he thinks,of no value 

 at all to any but a very few in each class. But in each case 

 it is necessary to supply a motive which the very young can 

 fully appreciate ; some terror must be held over the young 

 transgressor's head, and so long as terror is the motive 

 power, the stick is as fair as any other, with the advantage 

 that each culprit is an example to all who see his discom- 

 fort, and the influence upon them is nearly equal to that 

 of being caned themselves. The refined torture of solitary 

 confinement, which is considered less degrading, has not 

 this advantage. In like manner, everything in this world 

 is done for a prize, even if that prize be a " high caUing," 

 and school-boys require some outward and visible sign 

 of successful labour, books, marks, or class-places. The 

 grosser methods of marking it might well be dropped as 

 the children get older. But rewards we all strive for, 

 and it is untrue that no higher and wider valuation of 

 knowledge replaces the ambition to take home a prize 

 which first led to a laborious pursuit of it. 



W. Odell. 



ABSTRACT OF THE RESULTS OF THE IN- 

 VESTIGATION OF THE CHARLESTON 

 EARTHQUAKE} 



II. 



T ET us suppose an elastic wave to originate at a point 

 -*— C (Fig. i) situated at the depth q, below the surface. 

 Let the intensity of the shock (amount of energy per unit of 

 wave-front) at the distance unity from C, be denoted by a. 

 Since the intensity is inversely proportional to the square 

 of the distance, the intensity at the epicentrum would be 



.^. Take any other point on the surface of the earth at 



the distance x from the epicentre, and connect it with C 

 by the line Qx = r. The intensity at any such point will 



obviously be equal to —,. If we denote the intensity byj, 

 we shall then have the equation — 

 _ a _ a 



This equation expresses a curve which will serve as a 



' Paper read before the National Academy of Sciences at Washington, on 

 April 19, 1887, by C. E. Dutton, U.S.A., and Everett Hayden, U.S.N. , U.S. 

 Geological Survey. Continued from p. 273. 



