On the notice-board in the Captains' Room, the pulsing arrows of some twenty indicators register, degree by geographical degree, the progress of as many homeward-bound packets. The word "Cape" rises across the face of a dial; a gong strikes: the South African mid-weekly mail is in at the Highgate Receiving Towers. That is all. It reminds one comically of the traitorous little bell which in pigeon-fanciers', lofts notifies the return of a homer.
"Time for us to be on the move," says Captain Purnall, and we are shot up by the passenger-lift to the top of the despatch-towers. "Our coach will lock on when it is filled and the clerks are aboard."
"No. 162" waits for us in Slip E of the topmost stage. The great curve of her back shines frostily under the lights, and some minute alteration of trim makes her rock a little in her holding-down slips.
Captain Purnall frowns and dives inside. Hissing softly, "162" comes to rest as level as a rule. From her North Atlantic Winter nose-cap (worn bright as diamond with boring through uncounted leagues of hail, snow, and ice) to the inset of her three built out propeller-shafts is some two hundred and forty feet. Her extreme diameter, carried well forward, is thirty-seven. Contrast this with the nine hundred by ninety-five of any crack liner, and you will realize the power that must drive a hull through all weathers at more than the emergency speed of the Cyclonic!
The eye detects no joint in her skin plating save the sweeping hair-crack of the bow-rudder--Magniac's rudder that assured us the dominion of the unstable air and left its inventor penniless and half-blind. It is calculated to Castelli's "gullwing" curve. Raise a few feet of that all but invisible plate three-eighths of an inch and she will yaw five miles to port or starboard ere she is under control again. Give her full helm and she returns on her track like a whip-lash. Cant the whole forward--a touch on the wheel will suffice--and she sweeps at your good direction up or down. Open the complete circle and she presents to the air a mushroom-head that will bring her up all standing within a half mile.
"Yes," says Captain Hodgson, answering my thought, "Castelli thought he'd discovered the secret of controlling aeroplanes when he'd only found out how to steer dirigible balloons. Magniac invented his rudder to help war-boats ram each other; and war went out of fashion and Magniac he went out of his mind because he said he couldn't serve his country any more. I wonder if any of us ever know what we're really doing."
"If you want to see the coach locked you'd better go aboard. It's due now," says Mr. Geary. I enter through the door amidships. There is nothing here for display. The inner skin of the gas-tanks comes down to within a foot or two of my head and turns over just short of the turn of the bilges. Liners and yachts disguise their tanks with decoration, but the G.P.O. serves them raw under a lick of grey official paint. The inner skin shuts off fifty feet of the bow and as much of the stern, but the bow-bulkhead is recessed for the lift-shunting apparatus as the stern is pierced for the shaft-tunnels. The engine-room lies almost amidships. Forward of it, extending to the turn of the bow tanks, is an aperture--a bottomless hatch at present--into which our coach will be locked. One looks down over the coamings three hundred feet to the despatching-caisson whence voices boom upward. The light below is obscured to a sound of thunder, as our coach rises on its guides. It enlarges rapidly from a postage-stamp to a playing-card; to a punt and last a pontoon. The two clerks, its crew, do not even look up as it comes into place. The Quebec letters fly under their fingers and leap into the docketed racks, while both captains and Mr. Geary satisfy them selves that the coach is locked home. A clerk passes the way-bill over the hatch coaming. Captain Purnall thumb-marks and passes it to Mr. Geary. Receipt has been given and taken. "Pleasant run," says Mr. Geary, and disappears through the door which a foot high pneumatic compressor locks after him.
"A-ah!" sighs the compressor released. Our holding-down clips part with a tang. We are clear.
Captain Hodgson opens the great colloid underbody porthole through which I watch over-lighted London slide eastward as the gale gets hold of us. The first of the low winter clouds cuts off the well-known view and darkens Middlesex. On the south edge of it I can see a postal packet's light ploughing through the white fleece. For an instant she gleams like a star ere she drops toward the Highgate Receiving Towers. "The Bombay Mail," says Captain Hodgson, and looks at his watch. "She's forty minutes late."
"What's our level?" I ask.
"Four thousand. Aren't you coming up on the bridge?"
The bridge (let us ever praise the G.P.O. as a repository of ancientest tradition!) is represented by a view of Captain Hodgson's legs where he stands on the Control Platform that runs thwart-ships overhead. The bow colloid is unshuttered and Captain Purnall, one hand on the wheel, is feeling for a fair slant. The dial shows 4300 feet. "It's steep to-night," he mutters, as tier on tier of cloud drops under. "We generally pick up an easterly draught below three thousand at this time o' the year. I hate slathering through fluff."
"So does Van Cutsem. Look at him huntin' for a slant!" says Captain Hodgson. A foglight breaks cloud a hundred fathoms below. The Antwerp Night Mail makes her signal and rises between two racing clouds far to port, her flanks blood-red in the glare of Sheerness Double Light. The gale will have us over the North Sea in half-an-hour, but Captain Purnall lets her go composedly--nosing to every point of the compass as she rises.
"Five thousand-six, six thousand eight hundred"--the dip-dial reads ere we find the easterly drift, heralded by a flurry of snow at the thousand fathom level. Captain Purnall rings up the engines and keys down the governor on the switch before him. There is no sense in urging machinery when Eolus himself gives you good knots for nothing. We are away in earnest now--our nose notched home on our chosen star. At this level the lower clouds are laid out, all neatly combed by the dry fingers of the East. Below that again is the strong westerly blow through which we rose. Overhead, a film of southerly drifting mist draws a theatrical gauze across the firmament. The moonlight turns the lower strata to silver without a stain except where our shadow underruns us. Bristol and Cardiff Double Lights (those statelily inclined beams over Severnmouth) are dead ahead of us; for we keep the Southern Winter Route. Coventry Central, the pivot of the English system, stabs upward once in ten seconds its spear of diamond light to the north; and a point or two off our starboard bow The Leek, the great cloud-breaker of Saint David's Head, swings its unmistakable green beam twenty-five degrees each way. There must be half a mile of fluff over it in this weather, but it does not affect The Leek.
"Our planet's over-lighted if anything," says Captain Purnall at the wheel, as Cardiff-Bristol slides under. "I remember the old days of common white verticals that 'ud show two or three hundred feet up in a mist, if you knew where to look for 'em. In really fluffy weather they might as well have been under your hat. One could get lost coming home then, an' have some fun. Now, it's like driving down Piccadilly."
He points to the pillars of light where the cloud-breakers bore through the cloud-floor. We see nothing of England's outlines: only a white pavement pierced in all directions by these manholes of variously coloured fire--Holy Island's white and red--St. Bee's interrupted white, and so on as far as the eye can reach. Blessed be Sargent, Ahrens, and the Dubois brothers, who invented the cloud-breakers of the world whereby we travel in security!
"Are you going to lift for The Shamrock?" asks Captain Hodgson. Cork Light (green, fixed) enlarges as we rush to it. Captain Purnall nods. There is heavy traffic hereabouts--the cloud-bank beneath us is streaked. with running fissures of flame where the Atlantic boats are hurrying Londonward just clear of the fluff. Mail-packets are supposed, under the Conference rules, to have the five-thousand-foot lanes to themselves, but the foreigner in a hurry is apt to take liberties with English air. "No. 162" lifts to a long-drawn wail of the breeze in the fore-flange of the rudder and we make Valencia (white, green, white) at a safe 7000 feet, dipping our beam to an incoming Washington packet.