'54 



SCIENCE. 



[Vol. XII. No. 295 



closed-circuit coil and the disk. These currents are in approxi- 

 mately the same phase. If the closed-circuit coil be placed at an 

 angle with the main coil, then there will be a rotation of the disk, 

 the rotary effort increasing until the angle between the coils is 

 forty-five degrees. The shaft of the disk is geared to a train of 

 counting wheels, which record the number of revolutions. On the 

 lower part of the shaft are light air-vanes to resist the rotation. 

 When, the closed-circuit coil is set, and we have an alternating cur- 

 rent passing through the main coil, there is a rotary effort on the 

 disk proportional to the current ; there is a resistance to the motion 

 due to the air-vanes and the friction of the pivots. It is found that 

 the result is a speed proportional, within narrow limits, to the cur- 

 rent passing in the main coil. The following figures are taken from 

 the test of a 40- ampere meter: — 



In the last case the meter was overloaded. It would seem rather 

 doubtful, however, even acknowledging the accuracy of the instru- 

 ment tested, whether the friction of the moving parts will remain 

 constant in use. Still experience must decide its practical value. 



BOOK-REVIEWS. 



A New English Dzcizonary on Historical Principles. Ed. by 

 James A. H. Murray. Part IV. Sections i and 2. Oxford, 

 Clarendon Pr. i°. (New York, Macmillan, $3.25.) 



We noticed the first instalment of this great work in Sciezice for 

 April 25, 1884, and we are now glad to chronicle the appearance of 

 the fourth part, completing the first volume (A and B) and begin- 

 ning the second. It is superfluous to praise the work, especially 

 after the high commendations it has everywhere received. It is 

 generally acknowledged to be the best dictionary of any language, 

 and when finished will be indispensable to every thorough student 

 of English. Both its etymologies and its definitions are up to the 

 standard of the best scholarship, while in spelling and pronunci- 

 ation it is probably as satisfactory as any dictionary of English can 

 be. The typography also is excellent ; the definitions, quotations, 

 and other items under each word being clearly distinguished by 

 different kinds and sizes of type. The number of illustrative quota- 

 tions taken from some five thousand writers of the past seven cen- 

 turies is immense ; and in this respect, as well as in others, the 

 work will serve as the basis of all English dictionaries hereafter. 



The number of words in the first volume is 31,254, of which 

 15,123 are under A, and 16,131 under B. Some of these, however, 

 are merely variant forms or inflections of the main words, wjiile 

 others are special combinations explained under the main words ; 

 so that the number of main words alone is only 22,232, of which 

 12,183 are under A, and 10,049 under B. In a dictionary dealing 

 with seven centuries of English literature there are necessarily 

 many obsolete words ; and yet it is found, that, " of the whole Eng- 

 lish vocabulary on record since the twelfth century (so far as A 

 and B show), more than three-fourths is still in current use." The 

 development of the language in recent times, however, has been 

 great, owingchiefly to the progress of physical science and the 

 consequent introduction of new scientific terms. Yet the dictionary 

 does not contain by any means all the terms used in science, but 

 only such as are used more or less as English words ; the generic 

 names in natural history, for instance, being mostly excluded. 



In a dictionary based on historical principles, the subject of 



etymology is especially prominent ; yet to ascertain the origin and 

 derivation of some words has been found impossible, and the editor 

 thinks that they are comparatively recent creations of the English- 

 speaking peoples. Among such words he mentions 'bang,' 

 ' blight,' • blot,' ' blunder,' ' blunt,' • bounce,' ' bunch,' and many 

 others. One of the most valuable features of the work is the en- 

 deavor to trace, so far as possible, the derivation of the various 

 meanings of a word from the original one. This subject is of great 

 importance as illustrating the history of thought, and has been too 

 much neglected by philologists hitherto. Sometimes the develop- 

 ment of meaning is simple and easy to trace ; but in some cases it 

 is quite difficult, especially when the development takes place on 

 divergent lines. For instance, the word ' canvas ' is from the 

 Latin cannabis ('hemp '), and the connection of most of its mean- 

 ings with the original one can be readily traced ; but, when used 

 for the act of soliciting votes before an election, the affiliation is 

 not apparent. 



The difficulty of preparing such a work as this dictionary is im- 

 mense. Its inception dates from a resolution of the English Philo- 

 logical Society passed m 1857, at the suggestion of the late Arch- 

 bishop Trench. But before the composition of the dictionary could 

 be begun, three and a half million quotations had to be made by 

 some thirteen hundred readers ; and the preparation of the work 

 itself has proved much more difficult than the editors anticipated. 

 Arrangements have been made, however, for more rapid progress 

 hereafter ; and Mr. Henry Bradley, who has been an assistant 

 editor hitherto, is now engaged independently on the third volume, 

 so that some of us, at least, may hope to see the completion of the 

 work. 



Fads and Opinzo?is relating to the Deaf, from America. By 

 Alexander Graham Bell. London. 8°. 



The above is the title of a pamphlet containing much valuable 

 matter which Professor Bell collected in preparation of his report 

 to the Royal Commission appointed by the JBritish Government to 

 inquire into the condition of the deaf. No one is so well fitted to 

 be the spokesman of American activity in this direction as Profes- 

 sor Bell, and no one has proved himself more capable of increasing 

 our knowledge of the deaf as a class, and the means of improving 

 their condition. The report before us contains the answers of the 

 superintendents of American schools for the deaf to a long circular 

 letter drawn up by Professor Bell. Five general problems are dis- 

 cussed : (i) ' Visible Speech ; ' (2) the aural method ; (3) inter- 

 marriage of deaf-mutes, and possibility of a deaf variety of the hu- 

 man race ; (4) the self-supporting character of the education of 

 deaf-mutes ; (5) articulation-teaching. 



(i) With regard to the use of ' Visible Speech,' the fact that o 

 thirty-one institutions in which it has been introduced it has con- 

 tinued to be employed in only seventeen, argues against its univer- 

 sal applicability. The reasons for its dismissal are generally its 

 difficulty of comprehension and tedium of learning. None the less, 

 its hearty indorsement by so many superintendents shows that it 

 has more in its favor than against it. 



(2) The question of developing latent powers of hearing, and 

 especially vocalization, in persons usually termed deaf but really 

 only hard of hearing, is discussed at great length, with the general 

 conviction that much more can be done in this direction than is 

 usually understood. The good done in this way is not only a more 

 or less questionable improvement of the physical hearing, but very 

 markedly a direction of the attention to a class of sensations usually 

 neglected, and thus increasing the accuracy of their perception. 

 The mechanical aids to securing for the deaf a semi-hearing of 

 their own articulations are various, and variously valued, though 

 all seem susceptible of improvement. 



(3) Doubtless the most important topic of the inquiry is that 

 concerning the heredity of the deaf-mute class. Professor Bell, it 

 is well known, has written a memoir urging that the tendency of 

 the too close association of deaf-mutes with one another, as is now 

 in vogue, is towards the formation of a deaf variety of the human 

 race ; his statistics proving that a constantly increasing proportion 

 of the descendants of deaf-mute parents are deaf-mutes. The 

 superintendents of schools, however, maintain that the bulk of their 

 experience is against the truth of this thesis. Many recommend 



