410 



SCIENTIFIC NEWS. 



[May 4, 1888. 



have to do that, if double the current proposed is sent 

 through them, their temperature must not exceed 150° F. 

 They should be visible and acccessible, and when within 

 buildings they should be insulated, as also the parts of 

 fittings which have to be handled. The insulating 

 material should be damp proof, and should not soften at 

 a temperature under 170° F. Even the depredations of 

 rats and mice have to be provided against by encasing 

 the conductors in some suitable hard material. Gas and 

 water pipes must not be used as part of the circuit, as 

 their joints are rarely electrically good and therefore 

 become a source of danger. In the case of overhead 

 wires, every main should have a lightning conductor at 

 each point where it enters a building. It is also recom- 

 mended, as we ourselves have urged, that the positive 

 lead should be coloured differently to the negative. 



Electrical fittings generally, switches, commutators, 

 resistances, bare connections, lamps, etc., should be 

 mounted on incombustible bases. Vulcanite bases are 

 undesirable in damp situations, and the cracking of porce- 

 lain and earthenware fittings is a source of danger, unless 

 precautions are taken in the fixing. All circuits should 

 be protected with cut-outs, and all leads from 

 the mains, or small conductors from larger ones 

 must be fitted with cut-outs at their branching points. 

 Arc lamps must be guarded by lanterns or netted globes, 

 so as to prevent danger from sparks and from falling 

 glass or pieces of incandescent carbon. Dynamos should 

 always be fixed in dry places, and both primary and 

 secondary batteries should be placed and used with 

 the same precautions as prescribed for dynamos. Special 

 care is also necessary when " Transformers " are 

 used. In conclusion, it is pointed out that the value of 

 frequently testing and inspecting the apparatus and 

 circuits cannot be too strongly urged as a precaution 

 against fire. Cleanliness of all parts of the apparatus 

 and fittings is also essential to good maintenance and 

 efficient working. The risks of fire from electricity are 

 not nearly so great as with gas or oil, provided 

 the above points are attended to, and the moral of 

 the Society's useful lesson is that competent electricians 

 should always be employed to supervise the fitting up 

 of the electrical appliances. 



— ♦-^»^^fe^ — 

 SCIENTIFIC TABLE TALK. 

 By W. Mattieu Williams, F.R.A.S., F.C.S. 

 "At a recent meeting of the Physiological Society of 

 Berlin, Herr Meyer " discussed the nature of ventrilo- 

 quism, and combated the opinion so widely spread among 

 physiologists, that it consists in speaking while inspiring, 

 and without the cavity of the mouth acting in any vi'ay 

 as a resonator." He described a number of experiments 

 and observations fully refuting the old idea upon which 

 the name is founded, viz., that the ventriloquist speaks 

 from the stomach or abdomen. He is himself a skilful 

 ventriloquist, and his own sensations, and the observa- 

 tions of Professor Gad upon him, prove that the abdomi- 

 nal muscles do nothing in ventriloquism, while, on the 

 other hand, Herr Meyer himself, by means of an 

 apparatus recording graphically the variations of air 

 pressure, proved "that the curve obtained when a sen- 

 tence is spoken in the ordinary way is in all respects 

 identical with one which is described when the same 

 sentence is spoken ventriloquially." The volume of air 

 expired in the latter case was, however, considerably less, 

 in the ratio of 9 to 13. 



My quotations above are from an abstract in Nature, 

 January 12th last, from which it appears that Herr Meyer 

 and Professor Gad are not acquainted with the work of 

 M. de la Chapelle, Censeur Royal 2A Paris, Member of the 

 Academy, and a Fellow of our Royal Society, etc., whose 

 conclusions concerning the abdominal theory and the in- 

 spiration and non-resonance theory were identical with 

 those above stated. His rather pedantic work was pub- . 

 lished in 1772, and his conclusions, both positive and 

 negative, were afterwards confirmed by a Committee of 

 the Academy of Sciences, and ultimately by the whole 

 Academy. 



The ventriloquists by whose aid M. de la Chapelle 

 made his researches were Baron Mengen, of Vienna, and 

 a grocer of St. Germain en Laye, both amateurs, and 

 perfectly candid as to their methods of producing the 

 illusions. 



Baron Mengen ridiculed the old stomach theory, and 

 stated that he owed his art to a natural propensity to 

 imitate the cries of animals and other sounds. This 

 broke out at a very early age of childhood, and presently 

 extended to the imitation of distant sounds by a sort of 

 suppression or muffling of the voice. His method of ob- 

 taining this effect he describes as follows : — 



" I press my tongue strongly against my teeth and left 

 cheek, and the voice which appears articulated by the 

 mouth of the figure (he here refers to a doll with which 

 he carried on humorous dialogues) is formed, in reality, 

 between the teeth and left cheek of my own. For this 

 I use the precaution to hold in reseroe in the windpipe 

 (' le gosier,' he says, but he really means the lungs, such 

 a reserve in the trachea being impossible) a sufficient por- 

 tion ot air either to sing or speak, without the stomach 

 or belly giving any assistance, and it is solely with that 

 portion of air in reserve — moderated, retained, and suf- 

 fered to escape with effort — that I produce the voice that 

 I wish to make heard. Add to that a quality in my tongue, 

 extremely subtile and rarely possessed, by means of which 

 I articulate all syllables and words (either singing or 

 speaking) without in the least moving the lips, and 

 taking great care to retain to the end of each period, 

 phrase, or sentence the air which comes from the lungs 

 for renewing of my respiration, which requires a very 

 good cliest." 



M. Saint Gille was similarly communicative, and being 

 near to Paris, was the subject of a long series of observa- 

 tions. The theory of M. de la Chapelle, confirmed by 

 the Academy, was that the sound varies in its effect on 

 the ear according to the distance or place from whence 

 it comes. But every sound that reaches the ear is a 

 sound that may be imitated. The whole art of ventrilo- 

 quism is the power of imitating sounds which we are 

 accustomed to refer to certain distances and certain 

 situations. M. de la Chapelle was at first deceived by 

 the ventriloquists. He tells us how on his first inter- 

 view with M. Saint Gille he was rather surprised and 

 alarmed at a cry from the roof of a neighbouring house. 

 After a while the illusion ceased, and he referred 

 sounds to the mouth of the speaker which, others hear- 

 ing them at the same time, referred to distant places. 



Having satisfied themselves on this point of mere im- 

 itation, the academicians proceeded to investigate how 

 it was effected, and concluded that bj' habit a power 

 over the larynx was acquired by which it could be 

 readily shut or opened in the required degree, with the 

 additional power, from flexibility of the tongue, to articu- 

 late within the mouth, or even at the back part of it^ 



