Читать книгу Peter Parley's Wonders of the Earth, Sea, and Sky онлайн

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You must have noticed in the picture the great length of his snout. In a jaw-bone of such amazing length which was to be applied to such violent purposes, it was necessary there should be great strength. There were two ways of obtaining this: one would have been by having the bones very hard and stout; but this would not do, because they would then have been so heavy that the animal would have found difficulty in raising his head to the surface of the water for the purpose of breathing, since it would have overbalanced the other part of his body. The other contrivance, which was the one adopted by the wisdom of the Creator, was to make the jaws consist of several thin bones, a, b, c, d, strongly bound together, and terminating in succession like the plates of steel of which a carriage spring is made. There are accordingly six of these bones thus disposed.

But this was not all, the principal middle bone marked b, instead of having its fibres run straight, parallel with the others, had them placed in a slanting position, and thus there was additional firmness given to the jaw by what ship-builders would call diagonal bracing, a contrivance that you may often see used in the construction of houses and ships.