Scientific.

New Zealand Mail, Issue 210, 18 September 1875, Page 5

Scientific.

A writer in the Educational Monthly says that if a thin section of coal be macerated in a solution of saleratus, and afterwards washed and submitted to the action of nitric acid, to remove mineral impurities, the microscope will shew that it is made up of vegetable cells. They, usually show no sign of structure, but occasionally fragments of old logs have been found. The change from wood to coal, in some instances, is not complete, as woody fibre has been detected by the iodine test. Temperature of the Stars. The spectroscope, in revealing the constituents of the stars whose light it analyses, also indicates a difference in the temperature of different stars a fact not so well known. According to a well-known astronomer, there appeared°to be three general classes of stars with reference to temperature ; those in which the metals are detected, which are not so hot as the first class ; and those in which the metalloids are found, which have a still lower temperature.

In . the early part of the siege of Metz, foraging parties brought in great quantities of vine leaves from the surrounding vineyards, on which they fed their horses. The leaves were eaten with avidity, and the horses grew fat and sleek—much better in condition than those fed on hay and straw. This has led to a chemical analysis of vine leaves, and it is found that a very large quantity of cane-sugar and glucose exists in the tissue. Mr. George Smith of the British Museum has recently examined some of the tablets found by him at Kouyunjik, and now in the above building. They form parts of a continuous series of legends giving the history of the. world from the Creation down to some period after the fall of man, with a number of incidents and explanations as to the origin of evil, the fall of the. angels, the wickedness of the serpent, &c., which are not included in the Mosiac account. There is also another series of legends of primitive history, including the story of the building of the Tower of Babel and the Confusion of Tongues. Mr. Smith intends to publish a translation of the legends. The Money Market Review says that a fact of some importance, as tending to, if it does not entirely, dispel the prevailing impression that the “ life” of a submarine cable is of a limited nature, was mentioned by Mr. John Pender, M.P., at the meeting of the Eastern Telegraph Company. He stated that the various sections of the Eastern system, with the exception of a shore end of a short line at Lisbon, which was undergoing repair, were in perfect working order. But of far greater importance, as affecting the future of submarine cable enterprise, was his announcement that the Suez and Aden section, which was laid in comparatively warm water, had improved in insulation by no less than 38 per cent., and the other cable.s of the Eastern Company from 45 to 77 per cent, in insulation power, which is, of course, the chief element in estimating their capacity for the transmission of messages. Mr. Pender further stated that , the cables longest laid have improved most.

EFFECT OF TIME ON IRON. Razors which have lost their keenness and their temper recover, like mankind, when given time, and opportunity to recuperate. A spring regains its tension when allowed to rust. Farmers leave their scythes exposed to the weather sometimes from one season to another, and find their quality improved by it. Boilermakers frequently search old boilers carefully, when reopened for repairs after a long period of service, to find any tools that may have been left in them when last repaired, and if any are found, they are almost invariably of unusually good quality. The writer, when a boy in. the shop, frequently, if denied the use of their tools by the workmen, looked about the scrap heap, and under the windows, for tools purposely or carelessly dropped by the men ; and whenever one was found badly rusted by long exposure it proved to be of the best of steel. One of the most striking illustrations of this improvement of the quality of wrought iron with time has recently come to the knowledge of the writer. The first wrought iron T rails ever made were designed °by Robert L. Stevens about the year 1880, and were soon afterwards laid down on the Camden and Amboy railroad. These were Welsh rails, and when put down were considered, and actually were, brittle and poor iron. Many years later these were replaced by new rails, but until quite recently some still remained on the sidings. When a lot of unusually good iron was required, some of these rails were taken up and re-rolled into bar iron. The long period of exposure had so greatlv changed the character of the metal that the effect was unmistakeable.