OCEAN GROPING.

Dominion, Volume 1, Issue 24, 23 October 1907, Page 9

OCEAN GROPING.

7 : HOW THE GREAT LINERS "HEAR" ■ _■ i THEIR WAY IN A FOG. c To those, who go down to-tlio sea in-ships j obably no aiscovery in recent timos has been■ < ' more importance, or tends more to savo j Fo,'than'that of tho' possibility of signalling ] om ship to ship, and. from . ship'to shore, by 1 mnd. It literally, when fully developed, j ill enable' steamers to "'hear" their way, - ndor all conditions of weather, and .particu- : irly in fog, just as well as; they now. see their ; ay on clcar nights by tho aid of the lights lat each ship carries, and- thoso distributed jund tho coast of every civilised country. Everyono who' has ■ mada" tho; trip "to Mar- . ate, returning after. dark,. must, (says the. oiul on. "Daily have'been struck by ■' lie easy way hi'which-the steamer seems to nd- her ■ way through what appears to be a laze of traffic, guided by the'lights on shore nd thoso carried by: the other vessels in the iver. What lights are to a . ship on clcar iglits, sound: signals will be'to her in foggy nd dirty woather.■ " " til Old Principle Newly Applied. Tho whole apparatus hinges oii \tho fact, ("liich,; has been known for a long time, but fa 3 only recently been practically . applied, hat- water is a good conductor of sound, The eadiest example of this of which tho writer-is ■ware is to be found usually at mineral baths, 'hero is nearly always pumping going on in ionnection with 'the baths, but under ordi-, tary. conditions the pump'is not heard. When indrcssing, for instance, -to. enter tile bath, me can very rarely hear, the pump, but imncdiately one is in the bath, if ono places inc's head under water, the pump is almost lainfiilly ovidentj, and an engineer could easly count the strokes had he a watch at land. •■■■■. For signalling purposes a bell is employed, mmersed some distance under tho water and inclosed in a chamber, : tho; hammer being worked Uncompressed air operated from the surface. The sound of this, strokes on the hell iro transmitted to a distance'of several miles, und can bo lieard by a suitable apparatus.I'lio hearing apparatus consists of a microphoney a modification of that wo : use every time we speak to tho telephone, enclosed in a chamber insido thi ship, and connected with the bridge by wires in the usual way. The microphone chamber is. Bled with a special liquid which tho inventors have found.to answer tho purpose best, and.thoro is, as at present arranged, "one chamber and one microphone.on oa'cli bow below the water line. In tho chart-house., on the bridge ,is a pair, of telephone receivers, similar to thoso we put to our cars when we talk through'tlio telephono oil shore, and a switch enabling tho receiver to be connected to either of the two microphones. The Lighthouse Bell. Several of tho lighthouses on the coast of America, and'some, tho writer believes, 1 on that of the United Kingdom, are fitted with bells as described above,-' which arc rung at certain intervals,' each' , lighthouse having ,a> different number of beats, so that any particular lighthouse is distinguished by: its bell, just as m clear w-oatlier it is distinguished by' t-'i j arrangement of its lights. An approaching ship can toll within a very close approximation, as mathematicians wouuld say, how itlies with regard to the lighthouse, because l the beli >vill be heard loudest in that microphono oii the side: of the- ship oil which the lighthouse is, and the officer of the watch can steer accordingly.' Similarly,' even with present appliances, tho direction or'an" approaching steamer can.' bo heard, in the same manner. If tho approach-' ing. ship is crossing from right to left, or, 'as soamon express it; from starboard to-port, tho noise of her screw will be; heard more' clearly in tho microphone attached to the right halid or starboard side of the ship than in that on tho other side, and so a valuablo guido is afforded enabling the ship with the .sound-, signalling, apparatus to clear"theotlior.' But-,: iu tho writer's.view thiss is only the beginning of things,' and it should bo possible," when the details have bwja, .worked, out, to know as exactly whero an approaching 'ship is in the densest fog, and the direction in which she is'approaching as on the clearest night. •" Port am! Starboard Lights. All ships.carry a red,,light at night. oil the left hand,;.or port, side, whiio' all steamers cariyj in addition, ;a white light showing on both sides..-. Neither of.tho lights can he seen astern, nor ,for some distanco towards tlio bons, the limit being w/iat sailors call two points abaft.tho beam,, a little astern of. her miJdle point..' So that when approaching a ship from astern no lights aro visible to the approaching ship, but her full lights are visible from tho ship approached. ■ . When two. ships are aproaching each other from opposite, directions,: end-on, each, ship will see. the other's two or throe lights, and can easily steer to keep oiit. of each' other's way. There .is a simple rule for this, and incidentally it ]may lie mentioned that the danger is, least in this'ease', provided that both ships aro properly handled. \ Tho danger, of collision arises principally from ships crossing 6ach other, and: for this also there are simple rules governed by what is cajled the rule of the road. Leaving out the. question of sailing ships for the moment, the ship which has the other, the crossing ship, on her otfn right hand (starboard) side, has to,kcep out of the way, and it does so by turning slightly to the right, or to starboard, presenting, her left side to tho.'other ship,, and the two run on parallel courses till clear of each other. In all cases, "except", tliat' of .steamer and.; sailing ship. crossing, each ship., presents her own left, or port, side to the other to clear'. . ' Bolls in Place of tights'. . Evidently-tho same thing could'bo "done by tho aid of sound signals. If each ship carried, say, a bell on one side, and a foghorn on the other side; arranged as described, steamers also : carrying—till sailing ships completely disappear—another sounding apparatus heard on both sides, when two ships approached each other the ''officer: on theyratch' on the, bridge would know by tho sound',-boll or: foghorn, whether it was his place to give way or-that of the other ship. - The oCicer of the watch on the bridge of tho ship whoso'duty it was to hold on her course, could also follow the other going through the necessary manoeuvres to get out of his way, just as he now does by watching licr lights, * and could bo- ready in caso of noglcct *oti' ths part of tho'other ship, to do whatever was necessary to clear his own ship. /•• ■' ; ; • ' . Steamships always keapj clciir of sailing ships, and tho officer of the watch of- n stoamer meeting a sailing ships knows that he has to give way,' anC bo also knows exactly how to put his helm to clear the other ship by tho colour of tho sailing ships light that, is visible. Similarly lie would know, by tin sound noarcst which way sho was crossing and which way to nut his helm to clear her. Whenever! a ship has to givo way to anothoi tho colour of the light of the other ship is on tho samo sido as that to Trhich tho'holm must be moved. Thus, whon a red light is soon on the right hand (starboard) sido,- tho helm is put to port, tho 3ide of tho light soon. Sinnlarlv, whon a sailing ship is crossing from port to' starboard, showing hor green. light, that carried on her starboard sido, tho steamer puts her holm to starboard to clear. This rule could bo. ; . followed.-quite as'easily with sound signals. 1 - At. Palmcrston North on Saturday -night a man in a state of intoxication wont into tho local polico station and mado up a bod for himselt on the floor with a oi overcoats. Oil Holiday he was raiianr-fd for mimical treatment. According to tho Rotorua' paper tho Pohutn geyser continues to give some fine displays. On Wednesday afternoon of last week it gavo an exhibition and again 'on Thursdaymorning, playing for over an hour on the last occasion. Next "'"day it did not erupt, but all. othor geysers wore very active. The Scottish railway companies liavp arranged to increase holiday''passenger lares which in some cases have been cut below the paying limit.