Whaling

In the novel Moby-Dick, Herman Melville explained the reason for the harpoon's effectiveness:

In most land animals there are certain valves or flood gates in many of their veins, whereby when wounded, the blood is in some degree at least instantly shut off in certain directions. Not so with the whale; one of whose peculiarities is, to have an entire non-valvular structure of the blood-vessels, so that when pierced even by so small a point as a harpoon, a deadly drain is at once begun upon his whole arterial system; and when this is heightened by the extraordinary pressure of water at a great distance below the surface, his life may be said to pour from him in incessant streams. Yet so vast is the quantity of blood in him, and so distant and numerous its interior fountains, that he will keep thus bleeding and bleeding for a considerable period; even as in a drought a river will flow, whose source is in the well springs of far off and undiscernible hills.

— Herman Melville, Moby-Dick, 1851^[8]

He also describes another device that was at times a necessary addition to harpoons:

All whale-boats carry certain curious contrivances, originally invented by the Nantucket Indians, called druggs [i.e. drogues]. Two thick squares of wood of equal size are stoutly clenched together, so that they cross each other's grain at right angles; a line of considerable length is then attached to the middle of this block, and the other end of the line being looped, it can in a moment be fastened to a harpoon. It is chiefly among gallied [frightened] whales that this drugg is used. For then, more whales are close round you than you can possibly chase at one time. But sperm whales are not every day encountered; while you may, then, you must kill all you can. And if you cannot kill them all at once, you must wing [injure] them, so that they can be afterwards killed at your leisure. Hence it is that at times like these the drugg comes into requisition.

— Melville, Moby-Dick^[9]

Explosive harpoons

The first use of explosives in the hunting of whales was made by the British South Sea Company in 1737, after some years of declining catches. A large fleet was sent, armed with cannon-fired harpoons. Although the weaponry was successful in killing the whales, most of the catch sank before being retrieved. However, the system was still occasionally used, and underwent successive improvements at the hands of various inventors over the next century, including Abraham Stagholt in the 1770s and George Manby in the early 19th century.^[10]

William Congreve, who invented some of the first rockets for British Army use, designed a rocket-propelled whaling harpoon in the 1820s. The shell was designed to explode on contact and impale the whale with the harpoon. The weapon was in turn attached by a line to the boat, and the hope was that the explosion would generate enough gas within the whale to keep it afloat for retrieval. Expeditions were sent out to try this new technology; many whales were killed, but most of them sank.^[11] These early devices, called bomb lances, became widely used for the hunting of humpbacks and right whales.^[10] A notable user of these early explosive harpoons was the American Thomas Welcome Roys in 1865, who set up a shore station in Seydisfjördur, Iceland. A slump in oil prices after the American Civil War forced their endeavor into bankruptcy in 1867.^[12]

An early version of the explosive harpoon was designed by Jacob Nicolai Walsøe, a Norwegian painter and inventor. His 1851 application was rejected by the interior ministry on the grounds that he had received public funding for his experiments. In 1867, a Danish fireworks manufacturer, Gaetano Amici, patented a cannon-fired harpoon, and in the same year, an Englishman, George Welch, patented a grenade harpoon very similar to the version which transformed whaling in the following decade.

In 1870, the Norwegian shipping magnate Svend Foyn patented and pioneered the modern exploding whaling harpoon and gun. Foyn had studied the American method in Iceland.^[13] His basic design is still in use today. He perceived the failings of other methods and solved these problems in his own system. He included, with the help of H.M.T. Esmark, a grenade tip that exploded inside the whale. This harpoon design also utilized a shaft that was connected to the head with a moveable joint. His original cannons were muzzle-loaded with special padding and also used a unique form of gunpowder. The cannons were later replaced with safer breech-loading types.^[12][13]

Together with the steam engine, this development ushered in the modern age of commercial whaling. Euro-American whalers were now equipped to hunt faster and more powerful species, such as the rorquals. Because rorquals sank when they died, later versions of the exploding harpoon injected air into the carcass to keep it afloat.^{[citation needed]}

The modern whaling harpoon consists of a deck-mounted launcher (mostly a cannon) and a projectile which is a large harpoon with an explosive (penthrite) charge, attached to a thick rope. The spearhead is shaped in a manner which allows it to penetrate the thick layers of whale blubber and stick in the flesh. It has sharp spikes to prevent the harpoon from sliding out. Thus, by pulling the rope with a motor, the whalers can drag the whale back to their ship.^{[citation needed]}

A recent development in harpoon technology is the hand-held speargun. Divers use the speargun for spearing fish. They may also be used for defense against dangerous marine animals. Spearguns may be powered by pressurized gas or with mechanical means like springs or elastic bands.^{[citation needed]}

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  Bomb lance whaling harpoon, pictured in 1878, prominent in the famous whaling legal case Ghen v. Rich
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  Harpoon mounted on a whaling boat in Alaska, c. 1915
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  Modern whaling harpoon