The Use of Tools a Distinction between Man and Beast.--All Men, however savage, use Tools, but none of the lower Animals can do so until taught by Man.--Tools needed to break up the Ground.--The Digging-stick of savage Life: its Use and its Efficacy in practised Hands.--Digging-sticks in Nature.--The Heart-urchin, and its Mode of digging in the Sand.--The Spade: its Shapes and Uses.--Natural Spades.--Fore-foot of the Mole and Mole-cricket.--The Aard-vark, the Ant-eater, and the Mattock.--Shears and Scissors a Sign of Civilisation, never being employed by Savages.--Mechanical Principle of Scissors, the Inclined Plane, the Lever, and the Cutting Edge.--Chinese Shears and the Pruning Scissors.--Use of the Inclined Plane.--The Diagonal Knife of the Guillotine.--The Shears in Iron-works.--The “Drawing Cut” of Swordsmen.--Jaws of the Turtle and Tortoise.--The Snapping Turtle and the Chicken Tortoise.--The Locust, the Cockchafer Grub, the Great Green Grasshopper, and the Wart-biter.--The Leaf-cutter Bees and their Nests.--The Chisel and Adze.--Structure of Rodent Tooth and Chisel.--Use of the hard Plate of Enamel or Steel.--Combination of hard and soft Materials.--Teeth of Hippopotamus and Hyrax.--Principle of the Adze.--Self-sharpening and Self-renewing Tools.--The Plane and Spokeshave.--Principle on which they are made.--The Spokeshave and its Uses.--The “Guard” Razor.--The Hoop-shaver Bee and its Nest.--Its natural Plane, and the Use which is made of it. Among the many points of distinction between man and the lower animals, we may consider the use of tools as one of the principal lines of demarcation. Man stands absolutely alone in this respect. There is no race of savages, however degraded they may be, that does not employ tools of some kind, and there is no beast, however intelligent, that ever used a tool except when instructed by man. As to the stories that are told of the larger apes using sticks and stones by way of weapons, they are absolutely without foundation, no animal employing any tool or weapon save those given to them by Nature. It is true that a monkey may sometimes be seen to take a stone for the purpose of cracking nuts which are too strong for its teeth, and to perform that task with great deftness; but such animals have always been taught by man, and had they remained in their own country, not one of them would have used a stone, were the nuts ever so hard. THE SPADE. We will begin our notice of tools by taking that which must have been the first tool invented by man. One of the principal duties assigned to man is the culture of the earth, and this he cannot do without tools, increasing their number and improving their structure in proportion to his own development in agriculture.