ITEMS FROM AUCKLAND

Dominion, Volume 3, Issue 792, 15 April 1910, Page 8

PROBLEM SOLVED, TURBINE THAT CAN REVERSE. (By Tclefrraph.-Suecial Corresuondent.l Auckland, April 14. A reversible turbine seems to be at last an accomplished fact, through the invention of Mr. John Harks, a young AuekImider. Tho invention is not in the stage of mere crude speculation, but has Ion;; passed tho stage of experimental infancy, ami can now be «?eu in full working order at tho maker's foundry. A large number visited tho foundry during tho day, and wero able to satisfy themselves .that Hie claims made for the Marks's high-speed reversible. Inrbino did not rest upon thin air. On first seeing the machine one is struck with its compactness. It weighs roughly'about three tons, and is in every w,iy very much smaller than ,the usual reciprocating engine of equal ■ power. It occupies ■ only about 7ft. by 3ft. of floor space, and the height from the bottom of the. condenser to the top .of' the steam chest is about 3ft. This saving of space is particularly advantageous when the engine is used for marine propulsion, which is one .of the chief uses to which turbines are put. On account of the inability of the turbine to reverse, it has previously been neces,sary to have n. separate engine to send the shin astern, but with the advent of tho new invention this drawback should bo overcame, i It has been. amply shown that' Sir. llarks's invention'will , do sJI that is demanded of it in this respect, for, in the' s 'presence of numerous, critical spectators. .it satisfied the tests applied. Time after time •ft was sent ahead at the rate of about 1000 revolutions a minute, and after the order had been given to go astern, within five seconds it was goin;j at full' speed in that direction. It was also reversed at different speeds and under conditions of work, being suddenly stopped when going at a very high speed and reversed very speedily. It was again stopped for a short space oE.time, and then started on the reverse motion, and i also stopped either ' ahead or astern at' all points of the cycle, and irestarted without any hitch occurring, the engine answering all demands made upon it without trouble.

The engine exhibited, was of 50 horsepower, and had a water pressuro of 1801b. to tho square inch. Another of its. advantages is its freedom from moving parts. In ordinary steam turbines there are a very large number of vanes attached to the rotor, and theso increase in number as the power of tho engine increases. Tho. Marks machine, of 50 horse-power, has only four blades, and this simple arraugeniont presents a striking contrast to tlie thousands of blades which are ordinarily part of the mechanism, of steam turbines. The blades of the ordinary turbine, it is well known, are very liable to be seriously injured, and are a never-failing cause of aunoyfinco and trouble. The vanes of the Harks turbine, of which two are in each cylinder, are made of solid steel, .and aro dovetailed into tho rotor, so that it would require a very groat force to injure them. There is, moreover, an almost, total absence of friction, which naturally results in a. great saving 'of power. Tho balance of the rotors, and tho small number of pnrts, is also a prominent factor iii reducing the vibration almost to vanishing point, and thus tho invention presents an immense advantage over many of the engines 'which are now used in marine. propulsion. ' As a result of the general simplicity of, design the cost of ■ construction will be very greatly reduced," and "may "-be brought down to' somewhere about half the cost of turbine engines at present in use. A principle has also been introduced into the construction by which extra power may be . instantly applied should. occasion arise. The advantago of this would be folly felt in any case where extra speed was required as, for instance, in a tinie"'of 'danger. On the whole, the economy ■ of the Marks'invention is hardly 'open to doubt, as ! the. steam can bo taken at highest boiler pressure, and exhausted "at atmospheric pressure, and, as all the steam power which passes through the 'vanes is made use of, every ounco of power produced in tho boiler has to do its duty. The patent has been applied for in 22 countries; and'it has already been received in 19. ■ ... .

SUBURB OF NEWMARKET. ■ At' a meeting of ' the .Newmarket Borough Council last night, the Mayor (Air. , E. Davis) raised the question of the : amalgamation of the borough, with Auckland .city,' by. asking that a -committee bo'set up to inquire into the subject with a view lo seeing if the Auckland City Council is favourable •to negotiating terms. Mr. \ Davis said that tho line of demarcation which divides Auckland city from' Newmarket was now completely invisible, and he felt that he .would ho wanting in his duty if he did' , not give Eerious attention to the matter.