IT is worth while, by the way, to remark how curiously similar are such parallels. I have already mentioned the very evident resemblance between the water-boatman, the water-beetles, and the human rower, the body of the insect being shaped very much like the form of the modern boat. I must now draw the attention of the reader to the similitude between the very primitive boat known by the name of Coracle, and the common Whirlwig-beetle (_Gyrinus natator_), which may be found in nearly every puddle. The shape of the insect is almost identical with that of the boat, and the paddle of the coracle is an almost exact imitation of the swimming legs of the whirlwig. And, as if to make the resemblance closer, many coraclers, instead of using a single paddle with two broad ends, employ two short paddles, shaped very much like battledores. [Illustration: WHIRLWIG BEETLE AND PADDLES.] [Illustration: CORACLE AND PADDLE.] NAUTICAL. CHAPTER III. SUBSIDIARY APPLIANCES.--PART I. General Sketch of the Subject.--The Mast of Wood and Iron.--Analogy between the Iron Mast and the Porcupine Quill.--The Iron Yard and its Shape prefigured by the same Quill.--Beams of the Steam-engine.--Principle of the Hollow Tube in place of the Solid Bar.--Quills and Bones of Birds.--Wheat Straws and Bamboos.--Structure of the Boat.--The Coracle, the Esquimaux Boat, and the Bark Canoe.--Framework of the Ship and Skeleton of the Fish.--Compartments of Iron Ship and Skull of Elephant.--The Rush, the Cane, and the Sugar-cane.--“Stellate” Tissue and its Varieties. Having now treated of the raft, the boat, the ship, and their various modes of propulsion and guidance, we come to the subsidiary appliances to navigation, if they may be so called in lack of a better name. First in importance is necessarily the mast; and the yards, which support the sails, are naturally the next in order. Then there come the various improvements in the building of vessels; namely, the substitution of planks fastened on a skeleton of beams for a mere hollowed log, and the subsequent invention of iron vessels with their numerous compartments, giving enormous strength and size, with very great comparative lightness. Then we come to the various developments of the ropes or cables, by which a vessel is kept in its place when within reach of ground, whether on shore or at the water-bed. Next come the different forms of anchors which fasten a vessel to the bed of the ocean, of grapnels by which she can be made fast to the shore, or of “drags,” which at a pinch can perform either office, and can besides be utilised in searching for and hauling up objects that are lying at the bottom of the sea. Next we come to the boat-hook, which is so useful either as a temporary anchor, or as a pole by which a boat can be propelled by pushing it against the shore or the bed of the water; and then to the “punt-pole,” which is only used for the latter purpose.