206 



SCIENTIFIC NEWS. 



[Mar. 2, iS 



presented to him. This experiment has often succeeded in 

 the author's vivarium, in which, in 1881, the frogs were 

 exposed throughout the summer to the persecutions of a 

 number of grass-snalces, to which they all ultimately fell 

 victims. 



We are here reminded of the phenomenon known as 

 " shamming death," not vmfrequently witnessed in many 

 departments of the animal creation, and of the state of 

 helpless panic into which horses and cats are thrown in 

 case ol a conflagration, so that instead of escaping through 

 open gates, they sometimes rush headlong to destruc- 

 tion. We may also in this connection remember the 

 superstition of the " evil eye," which still prevails in 

 southern Europe, in the East, and in many parts of Asia 

 and Africa. 



In the Middle Ages a fixed gaze was accounted one of the 

 many means by which the sorcerer could gaze a command 

 over his destined victim. In witch- trials the judges were 

 particularly cautioned to avoid catching the eyes of the 

 accused. 



It is well known that some years ago a series of 

 experiments were performed in public upon human 

 subjects under the painfully-absurd name of "electro- 

 biology," which was afterwards shortened by certain 

 quacks into " biology," and in that name — or rather non- 

 sense — is still used in certain circles. 



All these phenomena, and many more which we have 

 not the space to enumerate, were referred, by our late 

 friend. Dr. Beard, of New York, to trance, or to an approx- 

 mating condition, which he called the " tranciform 

 state." 



It must not, however, be supposed that all animals 

 when pursued or threatened by serpents are in any way 

 paralysed. When about eighteen years of age we had a 

 vivarium in which specimens of nearly all European 

 species of reptiles were confined. We have often seen 

 how, when a live mouse or mole was thrown in, all the 

 vipers were up in arms snapping at the warm-blooded 

 intruder. But the mice, though they had often been 

 caught in woods where vipers were far from rare, and 

 might consequently be expected to know and fear them, 

 did not appear stupefied or perplexed. On the con- 

 trary, they scampered about, seeking shelter among the 

 stems of heath and Ledum palustre until the fatal bite was 

 given. 



Many death-snakes seem to lurk, quietly watching 

 until some suitable booty passes within striking distance, 

 when it is bitten before it can learn that an enemy is 

 near. 



— ■*-J>tS>«^5<f-*' — ~ 



THE TESTING OF ELECTRICAL 

 APPARATUS. 



T TNDER the auspices of the directors of the Techno- 

 ^ logical Museum at Vienna, a most useful laboratory 

 has recently been opened for testing electrical appliances. 

 The programme has just been issued, and from this it 

 appears that the work will embrace experimental investi- 

 gations of dynamos as regards output, power consumed, 

 efficiency, and other matters. There will also be investi- 

 gations and reports on completed installations for lighting, 

 and power and photometric tests of arc and glow lamps, 

 as well as the calibration of measuring instruments and 

 the testing of primary and secondary batteries. The 

 tariff fixed for the work is as follows : — For testing a 

 dynamo, from ^i 4s. to £4; a glow lamp, 16s. to 

 jQi 4S.; an arc lamp, jQi 4s. to jCi. 12s. If the work is 



of a special nature, the charge is to be agreed upon before- 

 hand. 



In England, as in other countries, there are several 

 good school laboratories, but none which are conducted 

 by independent officials, and we trust that the above 

 example will soon be followed in this country. Elec- 

 tricity now plays so important a part in our affairs, and 

 as the varieties of apparatus are almost as numerous as 

 the competing makers, it is no doubt time that a pur- 

 chaser should have the means of ascertaining by inde- 

 pendent testing what is the real efficiency of the apparatus 

 he proposes to buy. There are too many soi-disant 

 electricians, who talk very glibly of volts and amperes, 

 and who make very startling statements about the out- 

 put of their machines, or the lighting power or durability 

 of their lamps, and the public should have the means of 

 putting these statements to the test of practical trials, 

 made by competent authorities. In the hands of certain 

 well-known electrical firms, purchasers are no doubt 

 perfectly safe,'but even for these makers it would doubt- 

 less be an advantage to have their apparatus " Hall- 

 marked," to prevent disputes arising with buyers. 

 Inventors who have not the necessary laboratory appli- 

 ances would also be greatly assisted if, for a moderate fee, 

 they could have their inventions properly tested. Many 

 mistakes and much needless expenditure of time and 

 money would thus be avoided. 



Experience has shown the great advantages to the 

 public, as well as to the gas companies, of having all 

 meters tested and certified by independent authorities, 

 and it is well known that the Observatory testing of 

 chronometers is good alike for the makers and the 

 buyers. 



We are aware that this subject has already been 

 mooted in this country, and we trust that, in the interest 

 of all parties, steps will soon be taken to establish a test- 

 ing laboratory, to be managed by thoroughly competent 

 and at the same time independent officials. 



In Paris an electrical laboratory will be opened 

 shortly. The buildings have been presented by the 

 Brothers Menier, and various manufacturers have lent a 

 steam engine, a gas engine, and electrical machines and 

 apparatus. The laboratory is endowed with the profits 

 of the Paris Electrical Exhibition of 1881, which amounted 

 to ^12,000. It is intended to give every facility to 

 private individuals and manufacturers of electrical 

 machinery for making researches which they could not 

 carry on at their own laboratories or works. It is also 

 proposed to standardise electrical measuring instruments, 

 and to supply with each instrument which has been 

 tested a certificate showing its limits of error ; also to 

 test electrical machinery generally, and to institute 

 researches which the International Society of Electricians 

 deem of sufficient general utility. 



Pyrogenic Marblite. — Under this name a substance has 

 recently been patented which is intended to supersede 

 marble, where the latter is liable to become scratched or 

 stained. The new substance is made in various thicknesses, 

 is homogeneous, and usually has one side polished. It pos- 

 sesses a very durable polish, and, unlike marble, is non- 

 porous, does not stain, and can be used where dampness 

 would destroy marble. It is recommended primarily for 

 shop-counters, tops of wash-stands, Turkish baths, and the 

 like ; but it would seem to be a very desirable material for 

 the tops of lecture tables, and laboratory benches, where 

 corrosive acids are in use, as these have no more action upon 

 it than they have on glass bottles. ■ 



