SCIENCE NOTES.

Otago Witness, Issue 2433, 31 October 1900, Page 62

SCIENCE NOTES.

— For many years chemists and scientific men have endeavoured to find a use for the waste heaps attached to the various glass ■ works of St. Helens, most- of their efforts be1 ing directed towards discovering a method of \ making serviceable bricks. It is only now, '.^however (says the Liverpool Courier), that "sDr Ormandy, a well-known St. Helens man .■of science, has, after much rf-s^earch and experiment, found a practicable means of using tthe waste heaps for this purpose. Matters lhave passed the c-xperimental stage, • and a 'iplant has been laid down at Messrs Pilkinpion's' works, where the process ,of manufacturing -the new bricks will soon be in full swing. I The great waste heap at ■chese nlate-glass -contains a million and a-half to.ns of spent sand, which >fs being added to at the vate of 1200 tons weekly. This, to be used in the making of the rew bricks, has to be mixed witl an equal quantity of other substances, and 'therefore if every week's waste hae to be consumed in the manner indicated, it

pieans that 800,000 bricks will ha\e to bo made every seven days — an enormous output, and pne which shows what a scope the new industry will have to develop bofore the million and a-half lons can be tackled at all. The anew bricks, which are to be introduced to •the world in the course of a few months, will not only .be t sed f oi ordiuary building purposes, but for special operations which have hitherto necessitated peculiar material

of their own.

— One of the articles in the Windsor Magazine deals with the wonderful developments that are being opened up in science by the electrical furnaces at Niagara Falls. So far, they have not yet succeeded in manufacturing diamonds in quantities, but the clay does not

seem far distant when even these will be shipped from the Falls in peck boxes. The origin of the discovery was as follows: — "Mr Acheson conjectured- that carbon, if made td combine with clay, would produce an extremely hard subsla'nce; and that, having

been combined with the clay, if it should in vhe cooling separate again from the clay it

would issue out of the operation as diamond. \3m therefore mixed a little clay and coke dush together, placed them in a < rucible, inserted 'the end of two electric light carbons into the mixture, and connected, the carbons with a dynamo. , The fierce heat generated at the points of the carbon fused the clay, and caused portions of the -carbon ta» dissolve. After cooling, a careful examination was made of the mass, and a few small -purple" crystals ,v/ere found. They sparkled with something of the brightness bi diamonds, anA wore so Sard -that they scratched glass. Mr Acheson decided at once that they could not be diamonds, but he thought they might be rubies pr~ sapphires. A litle later, though, when he pad made similar crystals of a larger size, he Jound that they were harder than rubies, scratching the diamond itself. He lhowed them to a number of expert iewellert*, phomists, and-geologists. They had so much the ajyjcarance of natural gem. that many,

experts to whom they were submitted without explanation decided that tney must certainly be of natural production. Even, so ! eminent an authority as Geikie, the Scotch' | geologist, on being told, after he had exa- ! mined them, that the crystals were manufacj tured in America, responded testily, 'These [Americans! What won't they claim next? j Why, man, , those crystals have " been in the earth a million years.' " —A. wonderful institution for the treat- | ment of consumptives is being built near the ; beautiful city of Palermo, in Sicily, where ! the inmates will be surrounded by temples, ' grottos, and marble statues placedUin lovely j grounds, which will be illuminated afc night Iby thousands of lamps. The treatment pur- | sued will be the modern one, embracing con- • etant fresh air and ample diet, while the cai pricious appetite will be ministered to by a French chef. In addition to all the other luxuries promised at this unique home for I consumptives, the patients will have the use |of a yacht of 300 tons. Accommodation for i about 100 patients will be provided, and the | profits of the concern, after all expenses have been paid, will go towards providing for the wants of poorer sufferers. — For several months past experiments have been conducted at Sassari, in Sardinia, by Dr Fermi, Dr Cossul-Rocca, and Dr titxmbau, for the purpose of ridding that town of the pests of mosquitoes with which it is oveirun. The doctors effectually destroyed the larvse by distributing vast quantities of petroleum in the swamps and other spots where the insects bred, and the mosquities were exterminated by chlorine and other powerful destructive chemicals. The doctors in their report consider it possible to free any town infested with mosquitoes by this means, provided it is not too unfavourably situated. — During the last two years some most interesting work has been carried out at Nottingham College, on the influence of saccharose or cane-sugar on the growth of plants. The aim of the experiment was to compare the increased yield produced by sugar on plants drawing their nitrogen from the air, with that obtained in the case of plants drawing their nitrogen in a combined form from ' the soil. - "briefly stated, the results of the investigation show that the leguminous plants with healthy root-nodules or nitrogen-fixere benefit by the application of small quantities of sugar to their roots. . Further, even in the case of those plants which are devoid of rootnodules, but are supplied with an abundance of combined nitrogen, an increased yield is noticed after the application of sugar to their roots. At the same time, it is found that where the plants are starving for want of nitrogen, the addition of sugar is actually injurious; in fact, it is possible to kill plants by the use of too much sugar. These results confirm those obtained some months ago by Winogradsky and Omeliansky, who found that one part of grape-sugar in 500 entirely prevented nitrification. — Science Gossip. • — Dr It. E. Liesegang says that metallic silver occurs in fixed photographic films in several very different forms : in gelatine negatives we have a pure black form ; in printingout paper, fixed and not toned, a bright yellow kind. Observations of the development of faintly printed gelatino-chloride pictures with nascent silver prove that, besides the above kinds, there arc many oth^s, such as red, brown, olive, green, each in several dif ferent shades. As he has already pointed out, there is no doubt that the colour of the solver is only determined by the different sizes of the individual particles of silver which are embedded in the vehicle ; the finer the grain — that is to say, the few"er the molecules which combine to form a complex — the more the colour of the image tends to red or yellow. The black images are always considerably coarser-grained than the yellow and red. From observations he has made, he concludes that the colour Is only dependent on the size of the particles of silver. If a faintly-printed "aristo-type ' print (that is, gelatino-chloride of silver containing an excess of silver nitrate) is placed in an aqueou3 solution of gallic acid there is obtained, after ehort development and fixing, a yellowish-red print ; aftei long development, brown ; and finally green to greenish-black images. The longei the print htops in the developer, the larger the grain becomes by the accession of . nascent silver. That in this case nothing elsi can happen is well seen if a grintj. which

has been developed too long, is reduced with ■potassium ferrioyanide and hypo. The green form of the silver goes again into brown, and then into red. In the development of "gaslight" (Velox and similar papers) there is no accretion of metallic silver on the exposed grains of the silver haloid. The yellow and red tones appear then, if the paper is exposed for a long time, and if a diluted developer is used. The reduction of the silver haloid is then confined to the extreme outside of the individual grains. "With short exposure and development with a strong developer, the silver haloid grains, on the other hand, are finally reduced through and through, and the brown or greenish-black form is produced. It is possible, moreover, even with dry plates, which possess a very coarse bromide of silver grain, to obtain the fed form of silver by confining the reduction to the extreme outßide of the silver haloid. Sodium hyposulphite develops a chloro-bro-mide plate, which has been considerably overexposed, red, as do also some vanadium and molybolenum salts; but this last process is not, suitable for practical work. — That fatal disease, tetanus, or lockjaw, is propagated by the fodder of norses, which conveys the germ of it, and the Medical News of New York points out that, witb the advent of the motor car in cities, it will probably diminish, or even die out altogether. — tlichard Hilbert mentions the various conditions attending the phenomenon of coloured vision in Memorabilien. So far as lie is aware, his is the first report of a person seeing yellow after snake-bite. The following abstract of his narrative is given in the Medical Record: — "A young girl, walking barefoot in the fields, fell with a piercing cry that she was bitten on the toe by a snake. The snake was eeen by others. An hour later, when brought to the ofnoe, blood could be squeezed from the wound Tiear the nail. The next day there were stiffness and pain, besides the symptom that all light-coloured objects appeared bright yellow. A bluish discolouration of th© skin, extending over the abdomen, required 14- days to disappear. It was seven and a-half weeks before the child was well again. It would be interesting to learn whether in tropical countries, where snake-bite is more frequent, yellow vision is a common symptom." — One of the latest developments of modern science is a combination of phonograph and telephone. If you wish to go out for an hour you speak into your instrument, and if, while you are absent, you get a telephone call, the machine informs the caller-up that you have jtist stepped out to lunch, but that it will be pleased and proud to deliver any message. "When you return there is the message on the phonograph cylinder waiting for you. There are many advantages claimed for this ingenious system, but one of the greatest has apparently been overlooked by the inventor — namely, that it will be possible for the busy man who is rung up by a bore or a creditor to pretend to be his own phonograph, and thus escape haying to answer frivolous or awkward questions. The somewhat squeaky intonation of the phonograph can easily be imitated with a little practice.