SCIE.tifIC NOTES.

New Zealand Mail, Issue 1756, 1 November 1905, Page 56

SCIENTIFIC NOTES.

THE! NOTKIN DAMP. This lamp has been greatly improved of late, and the patent rights therein have been acquired bp the Patrolite Company, who are placing it upon the market in a great variety of different forms. * The essential part of the lamp is a container filled with indestructible, porous, absorptive material which is changed with the ordinary .petrol made familiar by motor-cars. The spirit is poured into the container and all surplus liquid drained hack again into the can. The container, when it is charged, is than perfectly safe, for there is no loose liquid; and even if a match be deliberately applied to it, it will burn quite quietly and in such a way that it can he instantly extinguished. The lamp is n appearance very much like an ordinary paraffin-lamp ; but in place of the dangerous and uncleanly paraffin reservoir there is a receptacle in which the charged container is placed. Above it is an ordinary incandescent-gas mantle. A lighted match held for a momentinside the chimney at the louver end crates a draught; air charged with petrol, vapour is'sucked up from the container below and ignites at the burner exactly as if it were ordinary gas, and the flame is regulated by means of a gas-tap. If the lamp he turned over it simply goes out,. because the draught is destroyed, and nothing further happens. It is believed that this lamp is far safer than an ordinary paraffinlamp, and the only element of danger lies in the charging of the container with petrol. That has now been reremoved by a- new and valuable device. A little connecting-piece is supplied, whereby the container can be screwed direct oil to the collar of the ordinary petrol-can. Can and container are then inverted for-a moment or two and turned back into their original position. By this means there is no fear whatever of spilling the dangerous liquid, and there is no time for vapour to escape and find its way to a source of ignition.

A STRANGE) GTJREi FOR SNAKEBITE, “Take a hair of the dog that bit you” is an old saav that, as a suggested remedy. has led many- a man out of the frying-pan into the fire, and it cannot certainly he recommended as a cure suitable for modern times, when an antidote is more re commendable. D'ogs are not, however, the only animals whose bite is to be feared; and those people whose travels have led them to far lands know that poisonous snakes are much more to be dreaded. Though by far the greater proportion of those pers ms thus bitten die, there is a certain number who recover, thanks to prompt measures, and thanks also to the administration of the exact remedy which any particular snake-bite requires. The poison ejected by the tooth of asps and serpents varies as much as does the poison from the spoken words of the wicked; and it has lately been discovered—especially in Brazil, which seems to hold the record for its variety of death-giving snakes—that the serum with which those bitten are treated should vary according to the kind of snake. Biut this, though advantageous to know in theory, is of small practical use, since the traveller cannot be sure of having exactly the right serum with him at the moment of the fatal bite. It has lately been reported that, on the principle of the old adage mentioned above—which thus serves a turn —an almost certain cure for snake-bite is the injection of a small portion of the bile of the reptile which has attacked any one, and which—the snake being generally killed on the spot—is naturally at hand. The gallbladder is extracted, its contents filtered, and the fluid injected under the skin. The method sounds somewhat complicated; but no snake-bitten person will complain if by this means he escapes a rapid death. The experiments .made have given the best results, those recovering from the poisonous bite of the South African snake coming off with nothing worse than an Jbcess at the point of penetration of the serpent’s tooth.

ELEQFRO-M agnetism in surgery. So much arrant nonsense has been written about the possible applications of magnetism to the curing of at least some of the ills which human flesh is heir to, that the intelligent mind will at once evince much scepticism, on perceiving the above title. However, no miraculous curative powers are in this instance attributed to the magnet. Changes in the character of steels used for the construction of mechanical appliances have made it possible to drive lathes at a higher speed, and to this cause is dug the fact that occasional particles fly off the work in hand and enter the workman’s eye at much greater velocity than used to be the case under the older conditions. The electromagnets which were formerly used to draw out these pernicious particles are not strong enough to extricate splinters of hard steel embedded deep in the homy substance of the eyeball. A huge electro-magnet has recently been constructed in America with a view to treating such cases. It is too heavy to lift about, and is therefore bolted securely to the floor in an upright position The iron core is four feet high and has a diameter of six inches, and it is tapered to a point at its upper end in order thait .its effects may be more easily watched by the oculist in charge. To w r ork it to its fullest capacity requires an electric equal to that consumed by about sixty sixteen-candle-power lamps. Not only does it effectually perform its delicate work, but it also in some cases obviates the use of the surgeon’s knife. For instance, a portion of a hammerhead had embedded itself in the muscles of the upper arm, and in another case a piece of cold chisel had flown into the forearm and burrowed deep in to the flesh. In each ease the moment the current was switched on the piece of metal was found adhereing to the pole-piece of the magnet, having almost instantaneously left its inconvenient resting-place by the route by which it had entered. It is suggested that this means of extricating from the human body pieces of steel and iron which have no businesstbere might be very usefully employed by army surgeons on the field of Battle. No doubt it would be efficacious in the case of splinters of steel shells, but upon the leaden bullets it would of course have no effect. Tire huge magnet is also useful as a detector of tsteel or iron partic'les in the body, for it is only necessary for the patient to walk within the magnet radiations and the pain of movement induced by the attraction of the magnet will at once reveal the exact position of the splinter.

IMPROVED ELECTRIC LAMP. One of the principal drawbacks in the electric light ha.s hitherto been the impossibility of turning it ,up or ■down, as the occasion required, after the manner of gas, so that a “peep” may be left, when the full /glow is not required. This difficulty has .now been overcome by the introduction of the “Economical Turn-down Lamp,” which is said to be used all over the United States and Canada, and is finding its way into Great Britain. The lamp contains two filiaments. one bright andl the other dim; and these maty be brought into use as required, either by nulling the string or by turning the bulb to right or left, as a bright, or a dim light is required. The thing is simplicity itself; and it is claimed for the lamp that there is a saving of 80 per cent, of current when only the small filament is used, and that it has a combined life of four times' that of an ordinary lamp. Of course this has to be taken with a - certain qualification, because users of the electriclight are not long in finding out that it may either be an economical or extravagant- illuminant in proportion as it is handled scientifically, so to speak, or clumsily, after the manner of gas-burning. But there is no doubt at all that a practical “turn-down” Lamp will be of immense advantage to consumers generally, and will enable them to rid themselves of the reproach that a house lighted electrically is usually in darkness! Such a lamp, it Ls easily conceivable, will be of greatadvantage to theatres and places of amusement where the lights have to be turned' down two or three times m the course of an evening’s performance although what is called a “dimmer” is in use at some such places already. A new type of this ingenious contrivance has just been introduced by Messrs Defines and Sons, the eminent lighting engineers, and will be installed on a somewhat extensive scale in the new theatre now being constructed for Messrs Maskelyne and Cook. It is claimed for this new form of “dimmer” that it avoids not ohly the * risk of interruption to the performance, but also of fire; and it is a curious oireumistanoe that of the entire equipment of the ill-fated Iroquois Theatre at Chicago tho only parts that remained uninjured were the ‘[Wirt” dimmers, which are now operating in the new theatre. It would seem that with the introduction of the new turndown lamp the only objection to the free use of the electric light in private dwellings is likely to disappear.— “Chambers’s Journal.”