A NEW PROPELLER.

Press, Volume XXXIII, Issue 4639, 14 June 1880, Page 2

A NEW PROPELLER.

id — d A paper by Captain Sadler, of the steamer « Stats of Indiana (Hall line), explaining the 18 invention of his double rudder and movable >d propeller .teamsbip, waa read at the United » Service.lnstitution on the 16th February, by fr Major J. M. Moody, 8.M.L.1. The following 38 ig a brief description of the invention, in Captain 18 Sadler's own words: —" The rudders are hinged -' on the rudder-posts in the usual way, with gudof geons and pintles. Both rudders aw in use at *s the same time, which gives double steering power it to the ship. The lower after deadwood is taken a- away, which enables the vessel to Bteer much -' more readily—going both ahead _ and asternal and at the same time admits solid water to the re rudders and propeller. - This also,allows the ir propeller to be removed from the deadwood and of stern—a point which the late Mr Froude ro strongly recommended, but which it is impossible of. to adopt in the preseat construction of steamers. -• The after end of the keel iB 3,4 or sft, wide, ache cording to the size of the ship, narrowed in to its it usual width at about 50ft forward. The propeller er is raised and lowered by two vertical screws rest- -~ ing on the keel, whioh can be worked by h_d or > n steam. The after carrying bearing blcck slides — up and down the stern-posts in guides, or can be 1T clamped round the Bternrpoatß. The journalat bearing block oscillates in this carrying bearing >y block. The after bulkhead is behind ; the'uniot versa! joint on the shaft, with sliding door >d (water-tight), and upon the shaft is an oscilm lating ball, moving m a socket attached to the are door." The universal joint is completely boxed is in and kept dry. . . . The reason why highly, powered ocean steamers'have such deep draught i- is to obtain immersion of the propeller; the tse proportions of vessels fitted with my patent m lowering propeller are not governed by this con'h sideration. They can, therefore, be made_ to *■ draw less water. The draught of water being -c reduced to obtain an equal displacement, the Br beam would therefore be greater; butu should s, recommend even a greater proportionate increase P of beam. Vessels built on this principle will c- also possess greater strength and be safer and a- better sea-boatß, because of the superior proporle tions of construction which the improvements ».ll referred to admit of. There will also be no Q - sacrifice of speed, no vibration of the ship, and th there will be the greatest possible immunity v- from accidents to the engines, which are freiie quentiy caused by their racing. Again,- there a- will be no thwartship bunkerp, the extra beam r, allowing sufficient room for all the coals in the sd gjje bunkers alongside the engine and boilers. ty The thwartflhip bunkers, when empty, are_ well >g known to be the principal cause of the-training ie of the vessel. Thia straining is caused by the nl irregularity of load, which is unevenly diatri- !- buted when the bunkers are empty. Its defect 'h. would not only be avoided, but the placing of the coal in the side bunkers opposite the engineß -d and boilers would be a great proteation to the t, machiaery and boilers of torpedo boats whilst re in action, and would enable the to merchant steamer to comply with the Adkh miralty regulations. Steamers, too, could be r- constructed on this principle so as to ia admit of being shifted in port without bal*r hut,, and even of croaeing the seas with little or r-. no cargo excepting coalfor the voyage out and al home. In case of any accident occurring to the a machinery at sea rendering steam as a motive c- power impracticable, the propeller can be raised re out of the water, and steamers constructed with in my improvements- could "then" proceed very. Br advantageously under sail; or, in the caße of a °t steamer going long voyages, such aa to Ausm tralia, when she got a fair wind the propeller s, could be raised, and the vessel would go nearly at as fast under sail as with steam, and save in is each trip from -3400 to £500 in fuel alone. 'y This arrangement would be of great advantage 1° to steam yachts. In addition to these-and id other advantages accruing to the. -merchant -t. service from the improvements; I venture ito >.c bring forward; steamers will be vastly superior 18 as passenger chips, inasmuch as the vibration, rolling, listing, and other discomforts which are , n now experienced in Transatlantic and similar is. voyages will be reduced to a minimum, and. the _;' greatest possible comfort secured." V '.'' '•' :