Grasping Tools.
Already we have spoken of the Shears and Scissors, together with their mode of action and dependence upon leverage. We now come to a set of tools which, although equally dependent on leverage, develop that power by grasping instead of cutting. Without these tools, the arts and sciences could have scarcely made themselves felt, as there are but few manufactures in which the artificer does not require a grasping power far superior to that of the human hand.
Perhaps the enormous power of the Pincers is never shown to better advantage than in the great iron-works, where enormous masses of white-hot metal have to be brought under the blows of the steam hammer. I do not know of anything which affords a more imposing realisation of the Divine command that man is to subdue the earth as well as to replenish it. There is the vast hammer, striking blows which are felt throughout a large area as if a succession of earthquakes had been let loose. In the furnace there is an enormous mass of iron, heated to such a degree that an unpractised eye could no more dare to look at it than to stare a midsummer sun out of face.
Where are the armies who are to cope with such forces? A few stalwart and grimy men come forward, each man with a curious but unmistakable air of one who wages a war of giants. The furnace door is opened, and out rushes a blinding light which strikes on the eyeballs like a shock of electricity. The men seize the handles of an enormous pair of Pincers, suspended in the middle by a chain, and though no unpractised eye can distinguish the glowing iron from the enveloping fire, they run the Pincers into the furnace, seize the iron, swing it to the anvil, and turn it this way and that way as easily as if it were a feather, while the blows of the gigantic hammer descend upon it, enveloping them in a torrent of sparks which spurt as if they were mere splashes of water, and seem to do them no more harm.
Taking the minor exposition of the Pincers principle and their use, we may mention the ordinary Pincers which are mostly used for drawing nails. Then there are the smaller Pincers called Pliers, all of which are constructed on the same principle, and the chief of which are the Round-nosed Pliers, the Long-nosed Pliers, and the Gas Pliers. Sometimes a mixture of the Hammer and the Pincers is ingeniously contrived, as in the tool which is represented on the right hand of the illustration.
Then we have the still smaller and feebler Pincers of civilised life, such as the Sugar-tongs and the ordinary Coal-tongs of our firesides. Anatomists could have had no practical existence without the Pincers, of which their beautifully constructed and much-elaborated forceps are but variations.
Take, again, the dentist, with his series of shining instruments, which he so carefully keeps out of sight until he has got his patient safely in that awful chair, and which glide, as by a conjurer’s trick, empty into an open mouth, and return in a few seconds with a tooth between their polished jaws.
All these instruments have their parallels in Nature, and in many instances the natural pincers might supply useful hints to modern tool-makers.
In the left-hand upper corner of the illustration is shown the common fresh-water Mussel, which is so plentiful in almost all our rivers and many of our ponds. Its scientific name is Unio margaritiferus. The latter title, which signifies “pearl-bearing,” is given to it because it furnishes the British pearls which were at one time so highly valued.
Like other bivalve molluscs, this Unio has the two halves of the shell fitting quite tightly upon each other, and, when they are drawn together by the contraction of the internal muscles, they can give a very severe pinch. In many uncivilised parts of the world the natives take advantage of this property, and use them as tweezers, chiefly for the purpose of pulling out hairs which they are pleased to think are not needed.
I need not state that with all bivalves the power is increased in proportion to the size of the shell. Even an Oyster can pinch most severely, while the Giant Clam, the shell of which weighs some four hundred pounds, could nearly take off a man’s leg if it seized him.
Mr. J. Keast Lord, in his “Naturalist in British Columbia,” relates an amusing story that was told to him by an old settler respecting the power of the Clam’s grip:—
“You see, sir, as I was a-cruising down these flats about sun-up, the tide jist at the nip, as it is now, I see a whole pile of shoveller-ducks snabbling in the mud, and busy as dogfish in herring time. So I creeps down, and slap I let ’em have it. Six on ’em turned over, and off went the pack, gallows scared, and quacking like mad.”
“Down I runs to pick up the dead uns, when I see an old mallard a-playing up all kinds o’ antics, jumping, backing, flapping, but fast by the head, as if he had his nose in a steel trap; and when I comes up to him, blest if a large Clam hadn’t hold of him, hard and fast, by the beak.”
“The old mallard might ha’ tried his hardest, but may I never bait a martin-trap again if that Clam wouldn’t ha’ held him agin any odds till a tide run in, and then he’d ha’ been a gone shoveller sure as shooting. So I cracked up the Clam with the butt of my old gun, and bagged the mallard.”
Of course the reader will remember that this was only an ordinary Clam, and not one of the giant race.
Below the shell are two very perfect instances of natural Pincers, each acting in a different manner, but on the same principle.
The Earwig is too familiar to need much description, but I may as well state that its pincers are not primarily intended as weapons, although they can be so used on occasion. (I was about to say, at a pinch, but refrain.) They resemble our ordinary pincers in that both blades move equally, and they are so completely under the control of their owner, that the insect uses them with a delicacy of touch that a lady’s fingers could hardly surpass. They are really tools, and not weapons, and are employed for the purpose of folding the wide and delicate wings under the tiny elytra.
There is another insect called the Scorpion-fly (Panorpa), the male of which is furnished with a pair of pincers at the end of a long and flexible tail, articulated just like the tail of a scorpion, and moved in exactly the same manner. It is but a little insect, but its gestures are so menacing as it flourishes its tail about, that non-entomologists may well be pardoned for being afraid of it. Moreover, small as are the pincers, they really can give a smart nip, and make themselves felt on the human skin.
If we want examples of exceedingly powerful pincers, we need only go to the Lobsters and Crabs, especially to the latter, whose claws are often of enormous thickness in proportion to the size of the animal. All those who have visited the seaside know how severe is the pinch of the common Green Crab, comparatively small though it be, and the same may be said of the river crayfish, which is, in fact, a lobster in miniature.
As to the lobster itself, fishermen are so well acquainted with the power of its claws, that they tie them together with string as soon as the animal is caught. Formerly they used to “peg” them, i.e. drive a wooden peg into the joint so as to prevent it from moving. This custom, however, is now prohibited by law on account of its cruelty.
The power of the Crab’s claws is so great that a bite from a large Crab will inflict a severe injury, and render a hand helpless. It has more than once happened that men who have been feeling for Crabs in the recesses of the rocks at low water have been seized, and seriously imperilled, not being able to release themselves from the gripe.
Indeed, it is said that there have been instances where the Crab has held so tightly, that the man has been drowned by the returning tide, no one having come to his assistance. I am, however, inclined to doubt this statement, thinking that the Crab would not be likely to remain in its hiding-place very long after the water came up. Still, that such an idea should be currently believed in many parts of England shows the estimation in which the gripe of the Crab’s claw is held.
TOOLS.
CHAPTER IV.
POLISHING TOOLS.—MEASURING TOOLS.
Files and Sand-papers.—The Sheffield File and its Structure.—The Equisetum, Mare’s Tail, or Dutch Rush.—Beauty of its Surface when seen through the Microscope.—Sand-paper.—Skin of Dog-fish, Skate, and Shark.—Skate-skin used for Sword-handles.—Distinction between the File and Sand-paper.—Measuring Tools.—The Plumb-rule and the Level.—Their Use in Tunnelling.—The Measure and its Uses.—The Two-foot Rule and the Tape Measure.—Ovipositor of Gall-fly.—Tongues of the Woodpecker, Wryneck, and Creeper.—The Spirit-level and its Uses.—Theodolite and Callipers in Nature and Art.—The Contouring-glass.—Pincers of Earwig again.—Jaws of Insects.—The great Sialis of Columbia.