Page:Popular Science Monthly Volume 91.djvu/217

 Popular Science Monthly

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��iary floats on the wing tips, and promises to defy the ocean successfully.

The difficulty of making any large air- plane relatively strong enough, although partly overcome because the unobstructed sea is an ideal starting and landing sur- face, still lingers in a certain relative de- ficiency in carrying capacity. On the other hand, there is a most welcome im- provement in equipment and comfort which permits, among other things, a liberal utilization of electric lights.

Heavy loads, however, cannot be carried without materially cutting down the radius of action — loads such as heavy guns and ammunition. With motors of 400 aggre- gate horsepower, a span of 92 feet and a total weight of 7,000- 8,000 pounds, this machine is expected to make from 55 to 85 miles an hour. So low a minimum speed is not objectionable on water. With only two men aboard, fuel for five hours might be carried.

All rudders and con- trols are worked by elcc tricity, and controlled most of the time, gyroscopically.

����Teaching Children Natural History with Animal Pictures Made of Sand

THE approved method of teaching very young children is to disguise the instruction under the cloak of amusement. An interesting development in the carrying out of this idea is found in the sand pic- tures of Walter A. Ward, of New York city. Cardboards covered with colored pictures of animals are given to the children to- gether with bottles containing the vari- ously colored sand. The children paint the body of the animals with glue, and then carefully cover the colored portions of the animal bodies with the appropriate colors of sand.

In this interesting way, while the chil- dren seem to be merely amusing themselves they are gaining very definite instruction as to the names, coloring and physical characteristics of the different animals. Stories in connection with their habits and the countries where they may be found naturally accompany the pictures and en- large the scope of the work. The rudi- ments of drawing and painting, as well as of Natural History, are indirectly taught in this way.

��Above: The larvae of the Automeris Io, the moth shown at the left. Its brilliant stripes and branching spines are its protection

��Sometimes an Object Is Beautiful Because It Is So Ugly

EVERYBODY is familiar with the ex- treme ugliness of the bulldog's face that makes the animal positively attractive ; and everyone who has studied the moths is familiar with the marvelous hideousness — or beauty — of the larva of the Automeris io. The Io is found from Canada to Florida and westward and southward to Texas and Mexico. In the larval stage it feeds on the leaves of almost any tree or shrub. For ages the enthusiastic lepidopterist has regarded it as a beautiful creature. The dainty green body with lateral stripes of pink and creamy white covered with clusters of branching spines forms an object to be admired — and respected too. It should be handled with care or painful consequences may result. Yet it is a curious fact that in spite of all the pains that Nature has taken to protect this beautiful creature from birds and other large enemies, she has left it open to at- tack from the tiny ichneumon wasp which drives its sting between the spines and there places a parasital egg. In this way multitudes of the larvaf are destroyed.

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