What a miracle of engineering the aerial galleons of Thanator represent! The long-ago invention of some forgotten genius of whelmed and conquered Zanadar, the great ornithopters are a marvel of the imagination somehow made real … and one of the many dreams of Leonardo da Vinci which have come true in the centuries after his time. After all, that most glorious genius of the Renaissance somehow envisioned the tank or armored car, the Gatling gun, that primitive precursor of the modern automatic weapon, the helicopter, and something remarkably like a cross between the pocket submarine and the diving bell. All of these the titanic vision of da Vinci pictured in graphic detail in his coded notebooks, leaving their eventual perfection to the mechanics and inventors of later generations. The ornithopter, or airship that flies by flapping its wings in imitation of a bird in flight, was one of his most amazing and revolutionary conceptions and the drawings of them in Leonardo’s notebooks anticipate the engineering problems involved with startling accuracy, visualizing them in vivid descriptive terms. My professors at Yale told me that the problems of human flight fascinated da Vinci for years, and that he struggled long to perfecta working model. It was, I suppose, the simple problem of weight which defeated his magnificent dream and prevented it from reaching fruition, and which brought to an end his superb effort to give wings to man centuries before the triumph at Kitty Hawk.
If only the divine Leonardo could somehow have spanned the ages and the gulf of space, to peer down through the brilliant morning skies of distant Callisto to watch as the great armada of the Three Cities floated on throbbing vans through the golden dawn―how enthralled he would have been, to see his splendid dream achieved at last by the denizens of an alien world!
The ponderous dimensions of the sky-ships alone would have amazed him. Frigates such as the Jalathadar measure some eighty-seven feet from stem to stern and are built very broad in the beam, flat-bottomed and portly; but otherwise their appearance and design is greatly reminiscent of the majestic galleons of the Elizabethan Age which once navigated the piratical blue waters of the Spanish Main. They are built quite high in the poop and the forecastle―the forecastle rising to about forty-two feet above the level of the keel and the poop or sterncastle a little less, some thirty-five feet―with a broad mid-deck, lined with a carven balustrade. About the only thing they lack for the Spanish galleon look to be complete is canvas, for of course they have no use for sails, and, hence, none for masts either. (They do have two masts, but short ones, and principally for the display of flags; observation stations are mounted like crows’ nests atop these short, stubby masts.)
The upper works of the forecastle bulge out sharply, an exposed belvedere giving a clear view on all three sides (and down, as well), and this belvedere opens into the pilothouse, with a balustraded observation deck mounted on the roof. The admiral’s stateroom is located directly beneath the pilothouse, with the captain’s quarters and the officers’ dining room (which also serves as council room) to either side. Further down the sloping curve of the forecastle, at about what would serve as the waterline on a seagoing ship, are two more observation decks or balconies, one situated on either side of the forecastle, and the sterncastle has a similar belvedere and rooftop observation deck giving a clear view to aft; just beneath this is situated the vertical rudder fin, ribbed like a gigantic Chinese fan; this is attached to the rudderstock which supports the belvedere and which is itself attached to the sternpost and thence to the aft steering gear.
From either side of the rather broad maindeck, which is the one feature about the vessel which lends it a slightly ungainly appearance―more like a fat goose than a graceful swan, you might say―the hinged wings extend. They are a part of the hull, and extrude to either side at right angles from slightly below the deck-level. These wings are quite solid and immobile for about two thirds of their full extent, but from thereon they are hinged in an ingenious and rather complicated manner, with enormous pulleys and guy-stays which manipulate the outboard wingsections so they do, actually, flap up and down in a ponderous fashion. The movements of these hinged sections, as well as the complex system of ailerons, are controlled from the capacious bold built directly below the central deck. There, stacked one above the other with narrow balconies and platforms at each level, are the ranks of enormous wheels which supply the motive power for the wingsections. Or perhaps I should say it is the wheel-gangs, whose task it is to turn these immense gears by hand, who supply the motive power. Turning these wheels communicates kinetic energy through an amazing system of sequential cogwheels, pinion wheels successively engaging with larger cogs, and the whole connecting with the guy-stays I spoke of earlier. These guy-stays are tough and thin as the finest grade of nylon cord you could buy on Earth (they are actually made of the silk of an enormous kind of spider). Perhaps I should remark here that a clever ratchet-and-pawl arrangement on the wheels prevents any sudden reversal―otherwise, of course, the first contrary gust of wind would strip the gears, which could be disastrous. These guy-stays are coiled about gigantic winches just above the topmost wheel-systems, and they communicate from the winches to the outboard wingsections through rows of circular ports in the hull. These ports, incidentally, ventilate the entire hold, or wheel deck, as it is called, quite admirably. Please don’t get the image of grimy, sweat-soaked wretches toiling at the oars in fetid darkness under the overseer’s lash―the sort of scene commonly found in the marvelous pirate movies popular when I was a boy. The wheel-gangs on an airship like the Jalathadar do indeed perform great physical effort, similar to that of groaning slaves plying the oars in the hold of a Spanish galleon. But they do it in air-conditioned comfort!
If such sky-ships were made out of wood, the weight would be prohibitive, on the order of hundreds of tons, surely. But they are not. Instead, they are fashioned entirely out of paper-layer after layer of tough, coarse papyrus-like paper, soaked in glue, stretched over molded plaster forms, and baked in ovens. When “done,” the plaster molds are chipped or broken away, leaving a hull-section molded of light, tough, amazingly strong laminated paper, from which the ships are put together. The Thanatorians also employ a powerful gas, like hydrogen, which fills the hollow double-hull (which is caulked until airtight, of course) and a series of airtight compartments in the bilge. The effect of this gas is to make the galleon almost completely weightless, just as in a German dirigible back in the First World War. The only known supplies of this natural gas were in the White Mountains, and they were destroyed when we conquered Zanadar. But recently the men of Tharkol found an even more capacious deposit of the gas in the Black Mountains near the south pole of Callisto.
The weightless effect of the stored hydrogen-like gas, of course, does much to render the galleons skyworthy. But the laminated paper construction is the real secret.
Who knows? If Leonardo da Vinci had known about papier-mache, the skies of the early Sixteenth Century might have been filled with such majestic aerial marvels as ply the windy heavens of Callisto!
The scarlet walls of Tharkol faded into the distance behind our sterns. The mighty armada of the Three Cities, cruising at about twenty-five miles an hour, floated due east at an altitude of about half a mile.