SOISNOE NOTES.

Otago Witness, Issue 2289, 13 January 1898, Page 48

SOISNOE NOTES.

• , • The fact that pigments containing arsenic are dangerous to the health is too widely known to require special mention. It has been especially found that arsenical wall paper, hung in damp rooms, has frequently caused chronic cases of poisoning in the occupants. There are two contrasting opinions as to the way this arsenic poisonicg comes about. Some think that the dast which becomes separated from the paper through wiping or coecussiou, aa well as expansion and contraction, caused by changes in the temperature, is scattered about and enters the lungs of the occupants, thus giving rise to poisoning. According to the views of others, the health ot the occupants of rooms provided with such arsenical wall paper is injured by arseninrottsd hydrogen gas, assuming that this is formed through the influence upon the arsenical substance of the paper of ojgan isms which appear when the organic binding agents, such as paste, &c, used for attaching the paper, become mouldy. To solve this question extensive researches have baen made for the first time by Emmerling in the laboratory of the Berlin University, the results of which seem to confirm the correctness of the first-mentioned opinion. It was shown that cultures of various bacterife, as well as several mould fungi, were not able to develop any trace of arssaiuretted hydrcgen from arsenical eubstrates. Nor did this gas form when paper with paste and Sshweinfurth's green, which is kaown to be highly arsenic 0, was exposed to moisture and became covered with an abundance or lsrge mould fungi. It may be assumed, therefore, that the first-mentioned opinion, which assigns the cause of the appearance of cases of chronic p^isoai»g to the pulverisation of the coating of the wall paper, is the correct one, unless still other undiscovered conditions enteric the matter.

■ . • A few months ago tha world was startled by the suggestion of an optimistic oculist that the blind might be made to e&e by means of the X rajs. Now it appears that these sanguine hopes have been, at, way rate in part, fulfilled by Dr Aftudillo, cf Havana. The m*n who has been cured was originally a resid«nt in Madrid, and ws? suddenly stricken blind 12 years ago. Eventually he camo to Cuba, where he gradually got poorer and poorer, until finally he was reduced to btgging. It was while (soliciting alms that he csine across Be A«iudillo, au oculist, who invited him to his house in order to see if anything could be done in his csse. After various expe; intents wi>h the X lays rhe patient was able to see different objsc'.s which were placed in the light. After fuither treatment he became able to differentiate between black and white in the daylight, and gradually to see and describe the machineiy of the apparatus', as well as connt the flashes of the incandescent lamps in the physician's study.

• . • Ifc has been pointed out by someone that if our esrth wore attended by several satellites icsfead of one, so that a full moon always rote whe-n the sun eel-, we should have thought that the universe only consisted of a few hundred stars instead of hundreds of thousands, for all the fainter stars would be put out of sight by moonlight. This simple instance "will perve to biing out the fact — long recognised by students of metaphysics — that we must not limit the universe to those objects and phenomena which come within our perceptions. Our ears are senfcitivc to sounds produced by vibrations bstween certain limits, and cur eyes to other vibraiiocs comprised within certain other limits, but otsviouply we must tiot conclude that no vibrations take place outside these limits. Sir William Orookes stated these limitations very clearly in an address lately published by the Society for Psychical Research. The lowest musical note which the average human ear can comprehend is produced by 32 vibrations pqr second, aad the highest by about 32,000 vibrations per second. Vibrations more

rapid than these canact be heard by us, though their existence admits o£ easy proof; indeed, animals having organs of hearing more highly developed than ours may communicate with one another by sounds of this character. Passicg from the air to vibrations in the omnipresent medium we call ether, the slowest of these manifest themselves as electric waves, Jai*-ly utilised for telegraphy without wires. From the highest electrical vibrations of this kiad to the lowest luminous vibrations there is a gap — an undiscovered region — which, ifc is reasonable to imppose, will some day be explored ; and there is a similar unknown region between the highest vibrations of light, and the vibrations v?hich possibly produce the X raya discovered by Professor Rontgen. There are thus two distitct gaps in the gamut of ethereal vibrations — two intervals in which wo seem to be as yet unablo either to sound the notes or detect them. The regions may comprise " brain waves," or bs in some way connected with the transmission of thought and intelligence from one person to another. Wild as this may seem, it is not beyond the bounds of legitimate speculation ; for it is certain that men of science are only now on the threshold of a vast domain, and that ethereal vibrations will be discovered having even more remarkable functions and capabilities than any yet investigated.

• . • We are so used to thinking of the soil as mere mineral matter that it comesquite as a shock to find this is a mistake. As a matter of fact the layer of soft mould which clothes the ground in a)l cul ivable districts, and from which vegetation springs, is actual'y in great part a living layer of tiny plants and animals. Inteilaciug threads of moulds and fungi, worms and grubs, creeping insects, tiny root parasites, decaying leaves, and tha millions of bacteria which spring from them — all the3e are mixed and mingled together for many inches down bslow our feet in a confused mass of life. Crarms of all sorts swarm in conntlsss millions. Indeed, all the plants that grow and life that exists on the face of the earth owe their being to the fact that the ground is alive. You take a shovelful of. the finest soil in the world and sterilise it — that is, heat it till all the life in it is destroyed — and then r>lant seeds in it. No amount of

cu'o or watering will make those seeds grow. Their life depends on the life in the soil around them.

' , • The highest recorded altitude ever E*aohed by a kite was obtained, on the af tsr-

coon of September 20, at the Blue Hill Observatory. The top kite reached tha height of 10,016 ft above sea level, or 83SGft above the summit of the hill. The ascent began at noon, and the highest point was reached at 17 minutes past i, when seven EUrgrave kites ware held by nearly fonr miles of wire. An instrument for recording the temperature, humidity, and pressure was hung about 130 ft below the highest kite. At the highest point reached tha temperature was 3S3f g, while at the ground it was 63deg. At the height of 4000 ft the humidity rose rapidly ; at 7000 ft the humidity was almost at the point of saturation ; at 8000 ft it began to fal), a nd at the highest point it was extremely low. At tha ground level the humidity remained low during tho entire ascent. Tha instruments and kites were brought down at 6.40 p.m., having been more than a mile above the hills for over five houi-3. — Scientific American. • . • A well-known scientist claims to have solved the problem of supplying the human mouth with false teeth which will grow into the guijs as firmly as natural ones. The teeth he supplies ara made of gutta-percha, porcelain, and metal, and are perforated at the root. H>>les are also made upward into the j-jw. The tooth ia then placed into the cavity. In a short time a soft granulated growth finds its way from the patient's jaw into the holes in the tooth. This growth gradually lmvdene, acd holds tha tooth in position. It is staged thafc it does not matter whether the cavity in which (.he tooth is to be placed is one from which a natural tooth haß beon drawn recently or whether it has been healed for some years.

• . • A curious ill os( ration of the power of light matter to perforate more substantial substances whea driven at a high velocity is seated by tho Engineer to have occurred recently in the Rpyal Arsenal. In ihs course of expeiimcfltp on firicg gas in tninea, conducted by Captain Oooper Key, R.A., under the Home Office, a special (run is employed to do duly for a bore-hole with a charge of high explosive, and pressed cylinders of raw dry clay Sin long and If-in in diameter are used to represent tamping. These "shots" are made to act in various mixtures of air, coa!-das f , gir-, Be?., and to stop the course of plug 1 , & j., eventually, v. ca-st-iron target plate, lifi thick, wss placed 25ffc in front at sn angl'? of iodeg, in order to break up evi-ry-thirg into dust and throw it upwards. After three or four shots! with this arrangement the clay plug, weighing 7£oz, perfora f ed the i«ch iron plat*, and the hole thus mode has b6en steadily exceeded since. The familiar tall.nv candle passing through a door mait bide its head before a 7£oz plug of clay perforating a>i iron plate an inch thick at <\n angle ot dSV-g. Doubtless the velocity mast be tre- , rr>endouf. It ia pointed out that, the vc-loci' y for a hard cylinder of this weight and eszo to cut through an inch of wrought iron at 45 ' eg would be over 1800 foot -seconds. With oast-iron and clay and the three or four repeated blows, everything is so greatly altered thab there is littls more to be said than that the effect is remarkable and unexpected.