This spider digs a burrow in the earth and lines it with a silken web. The burrow is closed by a trap door, having a hinge that permits it to be opened and closed with admirable accuracy. The door is circular, and is made of alternate layers of earth and web, and is hinged to the lining of the tube that leads to the burrow by a band of the same silken secretion. The door exactly fits the entrance to the burrow, and when closed, so precisely corresponds with the surrounding earth that it can hardly be distinguished, even when its position is known. It is a strange sight to see the earth open, a little lid raised, some hairy legs protrude, and gradually the whole form of the spider show itself. [Illustration: TRAP DOOR SPIDER.] The mode in which these spiders procure food seems to be by hunting at night, and in some cases by catching insects that are entangled in the threads that the creature spins by the side of its house. In the day time they are very chary of opening the door of their domicile, and if the trap be raised from the outside, they run to the spot, hitch the claws of their fore feet in the silken webbing of the door, and those of the hind feet in the lining of the burrow, and so resist with all their might. The strength of the spider is wonderfully great in proportion to its size. * * * * * TO MAKE A HOLE IN GLASS. _New Remedies_ describes the following easy method of making a hole in plate glass: Make a circle of clay or cement rather larger than the intended hole; pour some kerosene into the cell thus made, ignite it, place the plate upon a moderately hard support, and with a stick rather smaller than the hole required, and a hammer, strike a rather smart blow. This will leave a rough-edged hole, which may be smoothed with a file. Cold water is said to answer even better than a blow. * * * * * THE PRESERVATION OF EGGS. As science advances, the processes proposed for the preservation of organic substances are being brought to greater and greater perfection. No subject perhaps in this connection has received greater attention, and been the subject of more processes, patent and otherwise, than that of the preservation of eggs. In fact this is a question of considerable importance, not only from a culinary, but also from an industrial standpoint--that of the manufacture of albumen for photographic purposes. In the _Moniteur de la Photographie_ Dr. Phipson calls attention to a new process, which may be briefly stated as follows: