Page:Popular Science Monthly Volume 50.djvu/396

380 cocoons out with her on her hunting expeditions, attached to the spinnerets.

Last summer I kept a garden spider for three weeks under a tumbler, and had the pleasure of watching her building her house of snowy silk, with its three entrances, and raising a large family of children. She soon learned to take flies from my hand and drink water from a leaf which I gave her fresh every day. After a time she seemed to languish and droop, so I set her free in the garden once more.

says the old Kentish proverb.



ETROLEUM, asphalt, and bitumen may be regarded as so related to one another, so like in origin and properties, as to be callable of being considered in the same treatise; and we may, therefore, speak properly now of one, now of the other. The oldest known form of natural hydrocarbon was the bitumen which rose to the surface of the Dead Sea, called from that circumstance the Asphaltum Lake. Tradition says that it used to appear on the surface in considerable masses, and was collected by the Arabs and exported to Egypt, where it was used in embalming, and for a few purposes in the arts. The ancients were also acquainted with the liquid form of bitumen, petroleum. Herodotus speaks of the mineral oil of Zante; and other Greek authors mention the springs of Agrigentum, the product of which was burned in lamps, and was known as Sicilian oil. The fire worshipers of Persia erected temples over the burning springs.

Of the use of these substances in the middle ages, and later, we chiefly know that the petroleum springs of Pechelbronn, in the sixteenth century, spontaneously furnished mineral oil in such quantities that the peasants around used it to feed their lamps and grease their carriage wheels. The virtues of the mineral springs of the Jura Mountains were made known in 1712 by a Greek doctor, who pronounced them a treasure that had been unknown from the beginning of the world. Since then new sources have been discovered in all parts of the world, and the