January 13, 19 10] 



NATURE 



!5 



which are insulated from it. The resistance in series with 

 these discs is a metallic one, and obviates the trouble 

 iisually due to high resistances of graphite or carborundum. 



The first spark-gap is adjustable, and is enclosed in a 

 glass cylinder. Six or more sets of spark-gaps are con- 

 nected in parallel — each through a high-tension fuse — to a 

 <;ommon disc, which acts as one pole, while the cast-iron 

 base to which the columns are bolted acts as the other 

 pole. The columns are protected from dust and damage 

 by a glass cylinder, which rests on rubber pads on the 

 cast-iron base, and is protected on top by an insulated 

 cover. 



The characteristics of the electric valve may be summed 

 up as follows : — (i) absolute prevention of high-frequency 

 currents ; (2) unlimited capacity for dealing with any 

 energy ; (3) the adjustable spark-gaps being enclosed in 

 glass cylinders, there is no likelihood of dust getting 

 between the knobs and causing premature action of the 

 apparatus ; (4) the automatic extinction of the arc ; 

 X5) erection or dismounting very rapid. 



The Moscicki condenser resembles an extremely long 

 Leyden jar, with the difference that the neck of the jar — 

 where the coatings end — is considerably thickened. The 

 coatings are produced by a chemical silvering process, and 

 a heavy deposit on both the inside and outside of the jar 

 is obtained, which is further strengthened and protected 

 by a copper deposit. The jars are then mounted in a tin 

 or brass tube, on the top of which a high-tension insulator 

 is arranged, and carries the contact connected to the inner 

 ■coating. The outer coating is connected to the metal tube, 

 and the intermediate space is filled with a mixture of 

 glycerin and water. It is then hermetically sealed, and 

 consequently the condenser can be used in any position. 

 Class is used for the dielectric, owing to its great dielectric 

 capacity and uniformity. 



The usual type of condenser as used for line protection 

 •consists of a number of tubes, as described above, mounted 

 on a wrought-iron frame, and the inner coatings are con- 

 nected in parallel through high-tension fuses to a common 

 terminal, to which the line is connected. The outer coat- 

 ings are connected to the tin or brass tubes, and connected 

 to earth by means of the framework, which is so arranged 

 that each tube can be easily replaced or removed when it 

 is necessary. 



The design and action of both the electric valve and the 

 Moscicki condensers are clearly explained in a pamphlet 

 issued by Messrs. Isenthal and Co., of 85 Mortimer Street, 

 W., who have acquired the patent rights for both these 

 forms of apparatus for this country and the colonies. 



EDUCATION DURING ADOLESCENCE.' 

 "POR the vast majority of English boys and girls, our 

 system of n.'>tional education is a torso. It ends too 

 soon. It is a trunk without a head. How to remedy 

 this defect with practical wisdom, without expenditure so 

 immense as to provoke reaction, and with the convinced 

 cooperation of enlightened employers of labour, and of all 

 parents who unselfishly desire to further the best interests 

 of their children, is becoming one of the pressing questions 

 of the day. 



Out of some 1,300,000 boys and girls in England and 

 Wales who are between twelve and fourteen years of age 

 there are (to the best of our knowledge) about 211,000 

 (in addition to partial exemption scholars) who have 

 already obtained exemption from attendance at school, and 

 are receiving no further systematic education. Out of the 

 two million young people in England and Wales who have 

 passed their fourteenth birthday, but are still under seven- 

 teen years of age, only one in four (so far as our know- 

 ledge goes) receives on week days any continued educa- 

 tion. " The result " (I quote the finding of the Con- 

 sultative Committee) " is a tragic waste of early promise. 

 Through lack of technical training, hundreds of thousands 

 of young people fail to acquire the self-adaptiveness and 

 dexterity in handicraft which would enable them to rise 

 to the higher levels of skilled employment. Through lack 

 of suitable physical training, their bodily powers are in- 



1 From a paper on "The Relation of Elementary- Schools to Technical 

 Schools— Day and Evening." read at the Nonh of England Education Con- 

 ■ ference. Leeds, on January- 7, by Prof. M. E. Sadler. 



NO. 2098, VOL. 82] 



sufficiently developed, and their self-control impaired. 

 Through ' lack of general training, their mental outlook 

 remains narrow, their sympathies uncultivated, their 

 capacity for cooperation in civic welfare stunted and un- 

 trained'. In the meantime, modern industry, in some of 

 its developments, is exploiting boy and girl labour during 

 the years of adolescence. An increasing number of ' blind- 

 alley ' employments tempt boys and girls, at the close of 

 their day-school course, by relatively high rates of wages 

 which furnish opportunities of too early independence, but 

 give no promise of permanent occupation and weaken the 

 ties of parental control." 



The present state of things is not only intellectually 

 and economically wasteful, but often morally mischievous. 

 City life enhances the danger. Unskilled, or relatively 

 unskilled, employment at thirteen, with good money, 

 tempts a boy (and an increasing number of girls) like a 

 baited trap. A lad is drawn into a way of life which 

 leaves him at sixteen or seventeen without a trade to his 

 fingers, and with the habit of steady learning clean gone 

 out of his head. The years between thirteen and sixteen 

 or seventeen are the years of educational leakage. We 

 are like people who have laid down a costly system^ of 

 water supply, but have left a badly leaking pipe just 

 behind the tap. In order that our system of national 

 education for the masses of the people may bear better 

 fruit in personal skill and in civic value, the time has 

 come for us to secure a better foundation in the elementary 

 day schools and the continuance of wise educational attend- 

 ance during the years of adolescence. 



Differ as we may in judgment as to the legislative treat- 

 ment of the problem, we find, I think, but little disagree- 

 ment among ourselves in educational aim. Do we not 

 virtually concur in thinking that all boys and girls ought 

 to receive, during the years of adolescence, some form of 

 continued education which will develop their physique, 

 widen their mental outlook, cuhivate their sympathies, 

 prepare them for the responsibilities of parenthood, equip 

 them for trustworthy efficiency in the occupation by which 

 thev will earn their livelihood, and fit them for the duties 

 of citizenship? If this is to be done, it will be necessary 

 to mortise the work of the day and evening technical 

 classes into the work of the elementary day schools. We 

 need in the latter more training of the hand and of the 

 constructive powers, not with any prematurely technical 

 purpose, but as a necessary factor in brain development 

 and in a liberal education. This will not be possible 

 unless we have smaller classes in the elementary day 

 schools and unless the course of training for teachers can 

 be so prolonged as to permit training in educational hand- 

 work to be included in their course of professional pre- 

 paration without congestion of studies, without over- 

 pressure of mind, without encroachment upon the indis- 

 pensable liberal education, and without undue curtailment 

 of that mental leisure which is needed for all healthy 

 growth of interest, originality, and purpose. Nor do we 

 conceive of the technical class, whether day or evening, 

 as purely utilitarian or technological. Direct bearing upon 

 subsequent employment or occupation it must have. But 

 inseparable from its true educational influence is careful 

 regard for the training of the body, for the cultivation of 

 the sympathies and of the imagination by the love of 

 liter.iture, by music and by art, for an opening of the 

 mind to the significance of civic responsibility, and also 

 for those influences (often most powerful when least ex- 

 pressed in words) which help in forming a purposeful, 

 steadfast, and disinterested character. 



It is because the people's high schools in Denmark have 

 not only aspired to these aims, but have largely achieved 

 them, that they have raised the level of culture in the 

 whole nation and have indirectly, and. as it were, in by- 

 oroduct, enhanced the economic welfare of the people. 

 Nor should it be forgotten that the Danish high schools 

 do not receive children during the years immediately 

 following the day-school course, but are confined to pupils 

 above sixteen years of age. For this reason, the Danish 

 high schools are not at present fully gr.appling with the 

 problem of how best to continue the education of urban 

 children ; but the record and success of these schools may 

 well make us hesitate before embracing the conclusion 

 that, for children in the agricultural districts, attendance 



