The dinghy or longboat is an important plot element in 20,000 Leagues under the Sea that also presents an design challenge. Because it can be launched while the Nautilus is submerged, the dinghy provides the means of escape for the Aronnax party. Except for this essential plot element, there seems to be little reason to have such capability, although I like the idea of an emergency lifeboat. Perhaps Nemo originally conceived it as such for the Nautilus sea trials, when he used a skeleton crew. Later, seaworthiness established, he kept it as a novelty. This hypothesis does not address the telegraph, although that might have been added later.
Here are the relevant sections from the novel in the French and from Lewis’s translation. (Where necessary I've added the text omitted by Lewis.)
The dinghy is introduced in "All by Electricity":
« Elle aboutit au canot, répondit-il.
-- Quoi ! vous avez un canot ? répliquai-je, assez étonné.
-- Sans doute. Une excellente embarcation, légère et insubmersible, qui sert à la promenade et à la pêche.
-- Mais alors, quand vous voulez vous embarquer, vous êtes forcé de revenir à la surface de la mer ?
-- Aucunement. Ce canot adhère à la partie supérieure de la coque du Nautilus, et occupe une cavité disposée pour le recevoir. Il est entièrement ponté, absolument étanche, et retenu par de solides boulons. Cette échelle conduit à un trou d'homme percé dans la coque du Nautilus, qui correspond à un trou pareil percé dans le flanc du canot. C'est par cette double ouverture que je m'introduis dans l'embarcation. On referme l'une, celle du Nautilus ; je referme l'autre, celle du canot, au moyen de vis de pression ; je largue les boulons, et l'embarcation remonte avec une prodigieuse rapidité à la surface de la mer. J'ouvre alors le panneau du pont, soigneusement clos jusque-là, je mâte, je hisse ma voile ou je prends mes avirons, et je me promène.
-- Mais comment revenez-vous à bord ?
-- Je ne reviens pas, monsieur Aronnax, c'est le Nautilus qui revient.
-- A vos ordres !
-- A mes ordres. Un fil électrique me rattache à lui. Je lance un télégramme, et cela suffit.
"It leads to the
small boat," he said.
"What! have you a boat?" I exclaimed, in surprise.
"Of course; an excellent vessel, light and insubmersible, that serves either as a fishing or as a pleasure boat.''
"But then, when you wish to embark, you are obliged to come to the surface of the water?"
"Not at all. This boat is attached to the upper part of the hull of the Nautilus, and occupies a cavity made for it. It is decked, quite water-tight, and held together by solid bolts. This ladder leads to a man-hole made in the hull of the Nautilus, that corresponds with a similar hole made in the side of the boat. By this double opening I get into the small vessel. They shut the one belonging to the Nautilus; I shut the other by means of screw pressure. I undo the bolts, and the little boat goes up to the surface of the sea with prodigious rapidity. I then open the panel of the bridge, carefully shut till then; I mast it, hoist my sail, take my oars, and I'm off."
"But how do you get back on board?''
"I do not come back, M. Aronnax; the Nautilus comes to me."
"By your orders?"
"By my orders. An electric thread connects us. I telegraph to it, and that is enough."
|Aronnax first describes it in "The Black River":|
|Vers le milieu de la plate-forme, le canot, à demi-engagé dans la coque du navire, formait une légère extumescence. En avant et en arrière s'élevaient deux cages de hauteur médiocre, à parois inclinées, et en partie fermées par d'épais verres lenticulaires : l'une destinée au timonier qui dirigeait le Nautilus, l'autre où brillait le puissant fanal électrique qui éclairait sa route.||Toward the middle of the platform the longboat, half buried in the hull of the vessel, formed a slight excrescence. Fore and aft rose two cages of medium height with inclined sides, and partly closed by thick lenticular glasses; one destined for the steersman who directed the Nautilus, the other containing a brilliant lantern to give light on the road.|
|This passage in "The Arabian Tunnel" indicates something of its size:|
|En ce moment sept hommes de l'équipage, muets et impassibles comme toujours, montèrent sur la plate-forme. L'un portait un harpon et une ligne semblable à celles qu'emploient les pêcheurs de baleines. Le canot fut déponté, arraché de son alvéole, lancé à la mer. Six rameurs prirent place sur leurs bancs et le patron se mit à la barre. Ned, Conseil et moi, nous nous assîmes à l'arrière.||At this moment seven men of the crew, mute and immovable as ever, mounted the platform. One carried a harpoon and a line similar to those employed in catching whales. The pinnace was lifted from the bridge, pulled from its socket, and let down into the sea. Six oarsmen took their seats, and the coxswain went to the tiller. Ned, Conseil, and I went to the back of the boat.|
|In "Torres Strait" we learn more details of deploying the dinghy:|
Le lendemain, 5 janvier, le canot,
déponté, fut arraché de son alvéole et lancé à la mer du haut de la
plate-forme. Deux hommes suffirent à cette opération. Les avirons
étaient dans l'embarcation, et nous n'avions plus qu'à y prendre place.
A huit heures, armés de fusils et de haches, nous débordions du Nautilus. La mer était assez calme. Une petite brise soufflait de terre. Conseil et moi, placés aux avirons, nous nagions vigoureusement, et Ned gouvernait dans les étroites passes que les brisants laissaient entre eux. Le canot se maniait bien et filait rapidement.
The following day, January 5, the boat was uncovered,
pulled from its well in the platform and launched. Two men sufficed for this operation. The oars were in the boat,
and we had any only to take our seats.
At eight o'clock, armed with guns and hatchets, we got off the Nautilus. The sea was pretty calm; a slight breeze blew on land. Conseil and I rowing, we sped along quickly, and Ned steered in the straight passage that the breakers left between them. The boat was well handled, and moved rapidly.
Original text from Zvi Har'El's Virtual Library
The boat, described as small and light but large enough to hold perhaps a dozen people, is located by the text in the middle of the platform. There is no mention of a hoist and I could not see manually lifting a large, if light, boat and carrying it across the deck. Harper Goff, having already extensively modified the appearance of the Nautilus, was free to place the dinghy in a practical location at the aft end of the platform. From here it could be simply pushed away from the Nautilus. For my first design, I considered that position initially, but preferred to keep the launch between the wheelhouse and the lantern. Locating the launch at the side of the platform solve the launching and retrieval problem but introduced an uncomfortable asymmetry. Leo Arnold suggests mounting the boat sideways, thereby keeping it in the middle of the platform and allowing simple access to the sea. Greg Shape provides a davit in is second design.
In his latest, he employs a scissors and rail mechanism
for an up and out launch sequence. The boat is retrieved with the aid of a
retractable capstan. This allows launching by two people without a crane
or davit, but the approach necessitates moving the lantern forward.
|The dinghy has removable decking and a deck panel that can be opened after a subsurface launch. These, in addition to the submarine entry hatch and the attachment bolts, present a water tightness challenge. Greg Sharpe suggests flooding the interior below a certain depth, to protect it from pressure damage. The telegraph wire adds additional engineering complexity. The wire must be sufficiently long to allow maneuverability when the Nautilus is submerged at a reasonable depth, yet strong and light enough to prevent its breaking. Since the wire is not mentioned after its initial reference, I suspect Verne added it to lend credibility to the subsurface launch concept. I originally placed the wire reel on the Nautilus rather than the dinghy to keep the small boat as clean and simple as possible. Now I’m considering mounting it in the dinghy decking.|
My own new arrangement was inspired by Greg’s own second Deep Sea Designs Nautilus, which stows the dinghy bottom up. I initially missed the utility of this position. When the boat is attached to a hinged frame, it may be rotated to put it in the water, topside up. A stowable crank and a ratcheted gear train could be employed to rotate the frame to deploy and retrieve the boat, as shown in the simplified animation. With this mechanism it would be easy for two people to perform the operation for even a heavy boat. Strictly speaking, this approach violates the order of operation, since the boat is lifted from its cavity before the decking is removed, but it is so much more esthetic than my first solution that I prefer it.
Do you have an opinion? Please e-mail me.
26 Oct 99. This page and its
contents, except as noted, © Copyright
1999 Michael & Karen Crisafulli