SCIENCE AND ART

New Zealand Herald, Volume XXIII, Issue 7656, 5 June 1886, Page 4 (Supplement)

SCIENCE AND ART

According to the British Board of Trade, no fewer than 149 ships laden with timber have been totally lost within the laat few years. This explodes the theory that a ship loaded with wood cannot sink. The Tenacity of CoPPtR. —According to M. Guillemin, the tenacity 01 copper is greatly increased, even as much as 50 to 100 per cent, by the addition or a small percentage of cobalt. The alloys are all red. The old idea that slow grown timber was stronger than that grown quickly is disproved by recent tests, so tar, at least, as oak is concerned. Second-growth hickory is usually more valuable for handles of axes and hammer?, and the annual rings show it to be of swifter growth than the first s'.ock. Blotting Paper Foil Removing I>k Spots;. —In order to remove ink spots from paper take a thick blotting paper, sleep it several times in a solution of oxalic acid or oxalate of potassium and then dry it. If there is a spot to be taken away, apply the blotter ■which has been prepared in this fashion to it and the ink will be entirely removed. The little peachblow or crushed strawberry <ase which sold for over £4000 at the Morgan ,ale iB still the subject of remark in American itiat'.c circles. It was the chief feature oi Mrs. Morgan's collection of Oriental irt objects. The vase is eight inches n height and three inches in dia meter. It is ovoid in shape, with i short, slender neck, spreading slightly at the top. The peculiai peach-bloom colour of the vase i* what gives-it its value. It is of tht j.'ang-he period—l CGI to 1722. It he summer of ISS3 Mr. Kobertaon, of the American Art Association, while travelling in the East, arrived at I'ekin. Hearing of this valuable vane as being in the possession of I-wang-ye, a Chinese mandarin, he at once commenced negotiations with him for its purchase. Many months elapsed before he succeeded in procuring it, and many more ere he had it safely in New York. Mrs. Morgan wanted it, and got it ,for something over £3000. In hardly any depar.ment of wood-working can a greater saving in material be effected by the use of properly-designed machinery than in that of splitting up balks, especially those of the finer qualities. To meet the demand for such machines, the Egan Company, of West Front-street, Cincinnati, Ohio, U S.A., have introduced their improved baud re-saws. In this example the features of scrolling and re-sawing are combined in one machine. The change from one kind of work to the other is quickly made, and the machine is reported to do both kinds of work very effectively. The table slides back on a planed surface, and a few turns of a crank raises the six rolls. It is then ready for splitting, and will split &tuff up to 22 inches wide. The rolls being self-centreing, will centre any board. Rolls can be bevelled so as to split weather-boarding and any such work. The changing from splitting to scroll work is very quick and simple, and can be effected by one man in about a minute. Three changes of feed are on the cones. For resawing only the same frame is used, but the large table is omitted. In this way it re■awa logs up to 24 inches. The Egan Company's self-feeding rip-saws are a recent production, having been designed by the makers for use where a large quantity of ripping has to be done either in hard or soft wood. The chief features of improvement here are stated to be a reliable and powerful feed, much simplified and with much less machinery—a method of changing from a self-feed to a hand-feed and edger in one moment by loosening one thumb screw—a way of getting at the saw without disturbing the feed works by simply swinging feed-arm out of the way, and a method of feeding the piece so that it is always given a slight lead against the fence, and tracking the feed-saw in such a manner that ,the cutting blade always takes out the kerf made by the feeder. ! The feed consists of four speeds, 60, SO, 100, and 120 feet per minute, and it can be quickly changed from one to the other. The table is hinged at 'the back end, and, when the feedarm is swung back, can be raised up by the screw or clamp, or can be lifted clear up, giving free access to the mandrel and feed works. The cast steel mandrel is of best crucible steel, running in self-oiling boxes. The pulley is eight inches diameter, and 6i -nchea face, and should run 2000 to 2500 evolutions per minute, according to the size zof the saw used. The mandrel is fitted with asubatantial outside bearing, which allows of very heavy work being done with ease and jvit'hout strain on the machine,—lron.