Scientific and Useful

New Zealand Graphic, Volume XXXVIII, Issue 25, 22 June 1907, Page 42

Scientific and Useful

LONDON’S TUBES. London lias now six underground electric railways (tubes) in operation, and live more are under construction or projected. The railways of London, underground and surface, carry more than six hundred million persons each year, of which underground lines accommodate 258,000.000. There are nearly six hundred railway stations in greater London, and into the trunk line stations alone there pour annually more than three hundred million passengers. ♦ ♦ ♦ INDUSTRIAL I SE OF SEAWEED. According to a report of C. J. Davidson, of the British Embassy at Tok io, Japan, seaweed products bring in two million dollars a year. The coarser varieties of the vegetable are stewed and served with fish. Some of the delicate sprigs of sea grass are boiled with fish soups, and remain a vivid green, floating against the red lacquer of the soup bowls. Many other kinds of seaweed are used in the manufacture of glue, of plaster, and of starch. Whole villages are given over to seaweed fishing and the drying and the packing of the product for shipment to the manufacturing plants in the large cities. In the country along the sea-shore the farmers use the coarse and ropy kelp for fertilising their vegetable fields, in the last few years the Japanese Government has taken up the subject of the seaweed industry. Experiments have been carried on in many places along the coast, with a view to increasing the yield of the deep water algae. The Government* offers a reward for the best method of • producing iodine’ ffoih sea plants. ♦ ♦ ELECTRO-GULTURE. Summarising the progress that has been made in electro-culture, B. Tolksdorf, a German, finds it fairly well proven that electricity is essential to the growth of vegetation, although the important part played is not yet understood. Professor Lemstrom has found that plants soon died under a wire cage which excluded atmospheric electricity, while freely admitting air, heat and light. In Spitsbergen and Finnish Lapla ml, large crops are always connected with the early appearance of the Northern Lights; and in the experiments that have been made—so far on a small scale —the yield of many plants has been increased by an artificial supply of electricity aim water. It is supposed that electricity stimulates the sap exchange of plants, while Lemstrom has shown that it greatly magnifies capillary power, thus probably enabling the plants to take in more food from the ground. + ♦ > MACHINE MAY ABOLISH STENOGRAPHY. Plans now under way will make it unnecessary for business men to depend upon private stenographers or typewriters (says an American paper). Central typewriting exchanges, to which letters can be dictated over the telephone circuit and returned for signature in a few minutes, are to be. established in large office buildings and hotels in New York and other Eastern cities. Such a scheme has been made practical by means of the telegraphone, which not only makes a perfect reproduction of the human voice, but also records everything that passes over the ordinary telephone. These records are stored upon a thin steel wire or disc, and can Im* reproduced an indefinite number of times or removed when there is no further use for them. Each of the central exchanges will have a number of telegraphones and a staff of typewriter experts and trained lin-

guists. When the business man or the guest in a large hotel wishes to dictate he will pick up the receiver of his telephone and ask to he connected with a telegraphone in the exehange. By means of a small switchboard he will have complete control of the machine to which he is dictating in the exehange. If it should be necessary to make any changes in the letter, a push button is pressed, which brings a pair of magnets, stronger than those which made the record, into contact with the wire, and any part or the whole of the letter is immediately wiped out. In the same way records of dictated letters are wiped out as soon as transcribeu, so that the machine is always ready for use at any time. As soon as the dictation is finished the typewriter operator places the telegraphone sounders to his ears and transcribes the records which have been made, returning the letters to the office from which they were dictated. The matter transcribed might be in English, French, German, or any other language. It might be legal, scientific, or technical, full of difficult words and phrases which would tax even the most highlyeducated and expert stenographer to take down in shorthand with rapidity and accuracy. When the central typewriting exchanges are established, telegraphones will enable business men to dictate letters at a great speed, in any language, and on any subject. ♦ ♦ ♦ INFLUENZA IN WINTER. There is good reason to believe that the influenza bacillus is an air-pervad-ing microbe, and that infection takes plaee through breathing bad air rather than directly from one person to another. In this case the impure uncaused by large gatherings of people in badly ventilated public places would easily lead to a toxic concentration of the microbe in the air inhaled. The problem of providing fresh air for a large number of people in a confined space without producing an unpleasant draught has yet to be solved, but in the meantime, it is difficult to convice people that reinhaled, stagnant air is far more injurious in its effects than the dreaded draught. It cannot be gainsaid that draughts are not wholly innocuous, but susceptibility to a cold current of air is largely a matter of custom, and can be overcome. On the other hand, the spread of mierobic infection probably takes place rather through the accumulation of the organisms in the stagnant air of a public conveyance, a public gathering, or the home itself, than by direct contagion from one individual to another. It has even been suggested that the prevalence of influenza in winter may be accounted for by the fact that people then congregate in greater numbers in buildings and exclude air more rigorously in their dwellings. FISHY ELECTRIC LIGHT. Particularly fearsome are the fish that live in the lowest depths of the ocean over three miles down. There the pressure of the water is more than two tons to the square inch, and it is thus not surprising that the fish are not at all similar to the kinds with which most of us are familiar. Their bones are cartilaginous, in order to yield to the immense pressure to wmeh they are subjected; they arc almost all as black as jet, and every species known to science is of an incredible ferocity. In many cases their jaws resemble those of serpents, to permit of tneir swallowing objects— generally fish — broader than themselves, and the eel of those depths combines a huge size with the ferocity and voracity of the tropical shark. But the most remarkable point about the fish is the illuminating apparatus with winch taey are endowed by nature. This is in many respects similar to the most modern arc lights of human manufacture.