Once, when a boy of eleven, and consequently thoughtless, I set a chimney on fire by one of these Parachutes. I wished to see whether it would go up the chimney, and come out at the top. Unfortunately it was caught by a flame as it was launched, flew up in full blaze, and, as the chimney needed sweeping, the result was inevitable.
In the centre of the illustrations, and at the top, are two examples of a well-known natural Parachute called the Dandelion seed. The resemblance to the real Parachute is wonderful, the actual seed occupying the place of the car, and fulfilling the same office, i.e. keeping the seed upright until it reaches the ground.
When the tuft is closed, as is the case before the pretty ball of seeds bursts from the green envelope in which they had been confined during the process of development, its form bears the same startling resemblance to the Parachute.
Passing from the vegetable world, there will be seen three examples of Natural Parachutes. Several others will be mentioned, but we have no space for description or figure. It will be seen, however, that the one principle which characterizes them all is the exposure to the air of a flattened and large surface, in proportion to the size of the object.
Before beginning the description, however, I must mention that nearly all animal parachutes can to a certain extent guide their course, while neither the balloon, the gossamer, the parachute, nor the various winged seeds have the least power of guidance, but must follow every current of air in which they may happen to float.
The upper figure represents a Flying Squirrel.
There are many species of Flying Squirrel, but they all agree in one point. The skin of their sides is modified into a very thin fold, which extends as far as the feet.
It is very elastic, so that when it is not in use it falls into folds or wrinkles, and is hardly perceptible. But should the Squirrel wish to pass from one tree to another, without coming to the ground, it spreads its legs as widely as possible, so as to stretch the membrane into a wide, flat surface. It then boldly springs into the air, and sweeps upon its mark with a sort of skimming movement. Except that it does not revolve, it passes through the air much after the fashion of an oyster-shell when thrown horizontally.
Many mammalia are constructed after a similar fashion, such as the Colugo, or Flying Monkey, the Flying Mice, and the Flying Phalangists, or “Opossums,” as they are popularly called.