Progress in Science.

New Zealand Graphic, Volume XLVI, Issue 9, 30 August 1911, Page 48

Progress in Science.

A Novel Portable and Collapsible Mast.

s~i F GERMAN inventor has devised /I a very ingenious construction .JI of masts and steel bands running lengthwise of the mast and transverse connecting members for holding the steel bands together to form a tubular structure of square or polygonal cross section. \\ hile the general principle is the same for all sizes and types of masts, there are certain differences in the construction, according as the masts are to !><• portable or stationary. Portable masts are made in heights varying from 6 to 130 feet, wiith either four or six steel bands of best quality, their width being either I.}, or 21, or 4 inches. The bands are wound on four or sir drums, as the case may be. For very small sizes (up to 17ft) spring drums are used, and the mast is pushed up or drawn down by means of two {wheels the teeth of which fit into corresponding holes in two opposite bands* Tor the larger sizes, the drums are rotated by means of cranks, and the raising ot the mast is effected by means of a hoistirg device of various forms. In most cases the hoisting de\ ice is operated by one or more , ranks, which control either fraction wheels engaging opposite bands, or toothed hoisting wheels whi h fit into

holes of some of the With a mast comprising four bands two are operated in this manner, while a six-band mast has three of fits bands engaged by' toothed hoisting wheels. In the case of portable masts, the transverse connecting members consist of plates or frames arranged to surround and brace the tube formed by’ the longitudinal steel bands. When the mast is ‘completely’ (collapsed these nutmerous plates are stacked one upon the other and thus occupy very, little space. The uppermost plate is secured to the top of the mast, and the other plates are held together loosely by ropes or other flexible connections, so’ that the plates will be raised successively and automatically as the mast is extended upward by turning the cranks. A small ladder may be attached permanently to the plates to enable a person to dumb up or down readily. In the illustration a seat for the person ’is carried by the upper end of the mast: instead of this, there is provided sometimes a rotary table with a chair ami a stand for holding a telescope. Stationary mast 3 on thus principle are made in heights from 50 to 250 feet, and over, with four or six steel band* up to 14 inches wide and up to 1 5 of an inch tiiick. The. masts are raided by means

of simple hoisting devices, which for the smaller sizes are operated by levers rocked up and down as shown on this page; for larger sfczes the hoisting device is operated by cranks, as shown on the front page. Instead of being permanently connected with the steel bands’, as in the portable masts, the hoisting device is detachable, so that the same hoisting device may be used to erect different masts successively- The steel bands are not wound upon drums, but simply coiled upon themselves for convenience lin storing and shipping. Their edge« have teeth or projections which interlock, and iji some cases they also have peforations in the centre. Instead of connecting plates, two-part clamps are employed, these being applied individually as the structure rises, and drawn tight by means of screws to hold the steel bands together. The clamps may be formed with steps to faciliate climbing the mast. Stationary masts are set upon a suitably prepared foundation, and are generally braced by guy wires. The top of the mast may carry an extension made of steel tubing. I hese masts are used for a great vari-. ety of purposes, as supports or carriers for electric kvmps or searchlights. for wires or cables, as antennae for wireless telegraphy, as extensible ladders, as flagpoles, observation masts for military or naval purposes, signal masts or semaphores. for cranes and derricks, posts for scaffolds er buildings, etc. I he portable form of the invention present' obvious special advantages for purposes such as rescue work, for firemen. and railroads, where it will valuable on account of the quick eree* t’ion of the mast: its ready transportability. and the tact that in the collapsed state it may pass through places where it could not be brought fully extendedFor the same reasons, it will find ready

use in the army and navy for reeonno't. ering purposes, signalling, for carrying searchlights, periscopes, torpedo nets tents, sheds for dirgible balloons and for aeroplanes, etc.—"Sctientific American.” The Stone Age in America. There is a good deal of scattered material in museums and elsewhere relative to the stone age in North America, but so far attempts to reduce it to any satisfactory chronological order have not been very successful; :he objects, as a rule, are found on the surface or in mounds that cannot even be relatively dated. It is obvious that tribes of a thousand years ago used implements that can hardly be dislanguished from those of the glacial i. riod; while in the same tribe implements representing various stages of culture appear to have been in use simultaneously. The distinctions of period are thus by no means so clearly marked as they generally are in Europe. Most authorities agree that there is little or no evidence for the presence of paleolithic man in North America; he had probably been well advanced in the neolithic stage before the migration from North east Asia began. Even such a limit gives the historian of North America a good many thousand years to work in—much more ample ground than he is at present able to cover. Sound Proof Rroiu. The Physiological Institute of the University of Utrecht possesses one of the most remarkable rooms in the world, a chamber about seven and a half feet square, which is said to be absolutely noiseless, as far as the entrance of sounds from outside is concerned. This room is situated on the top storey of a laboratory building, and is an inside room, but so arranged that it can bo ventilated and inundated with sunshine. The walls, floor and ceiling e.i.-’i consist of half a dozen layers o' different substances, with air spaces and interstices filled with sound-deadening materials. Some persons when in the room experience a peculiar sensation in the ears. While every effort has been made to exclude sounds that are not wanted. of course the object of constructing this singular room was to experiment with phenomena connected with sound. Some of the sounds employed are made in the room itself, others are introduced from outside by means of a copper tube, which is plugged with lead when not in use. ❖ <?><?> The Palola Worms. A very curious life history is exhibited by the Palola worms. These are green-ish-looking seaworms, found among the crevices of the eoral rocks of Samoa, Fiji, and some of the Pacific Islands; while very similar species are also found in Florida and Japan. There is breeding season twice a year, when the waters are thick as vermicelli soup with tho little creatures, which, incidentally, are esteemed a great delicacy. The peculiar thing about them, 1 's-r, is that they have no heads. liny are simply the hinder segments of the worms laden with germ cells of b ’ll syxes, which are set free by the rupture f tho l.odv wall. The, head remains in its coral crevice. It has shaken off . - long tail—the Atlantic species is ab ut W inches in length—and proceed- to a new one. These worms ' a ord a remarkable instance of regem r >'a (,t lost parts. The fact that r r Suction by budding and fission is found a'nong some other Polyehaet wormsuggests the origin of this pc ili r characteristic. The Earth s Core. At a meeting of the Selsim sociation at The Hague, Pi ■ asserted that his studies of '< velocity of earthquake trenmi ■ ' ' J through the interior of the : 1 ■ ' ’ to the conclusion that the e.u a ■ of a central core of iron or .-!> I 5580 miles in diameter, surrom | a stony shell 930 miles In thi, km ■ 1 tween the outer solid rind an . ~ 1 f , layer of roek, covering tho I he thinks there is a layer of j<| I plastic material, lying a lilt''' * " , 20 miles below the surface of the ea -