The Wonder Book Of Knowledge Part 32

[Ill.u.s.tration: WIRELESS STATION ON A STEAMSHIP]

On the palatial pa.s.senger steamers that plow the Atlantic the Marconi apparatus enables the travelers to keep in touch with their friends, to transact important business on either side of the water, and to secure a continuity of life which was formerly divided by a sea voyage. All the larger vessels now publish a daily paper on board, the news in which has been supplied by the same agencies who feed the newspaper on land.

Information is flashed to meet or overtake the vessel and caught up by her aerial, as she pursues her way at twenty-five or thirty miles an hour.

In the case of cargo vessels, the owners are able to get into touch with them at any point of their voyage. They can advise the captain where to call for coal or cargo, while he on his part can get into communication with the authorities or his firm's agents at the port of call, and have every necessary or desirable preparation made for his arrival. Should an accident happen, he can call a.s.sistance, inform the owners or relieve anxiety and suspense. At no time is he isolated from the world. The fort.i.tude, courage and daring of those "who go down to the sea in ships"

has never been called into question, but it has if anything been emphasized by the receipt of messages from an operator at his post, to whom the bonds of duty were as bonds of steel, and who calmly operated the key until the waves entered his cabin and brought him honorable release.

[Ill.u.s.tration: U. S. BATTLESHIPS "NEVADA," "OKLAHOMA" AND "ARIZONA"

The latest type of super-dreadnaught for the United States Navy, with a displacement of 27,500 tons and engines of 28,000 horse-power.

NOTE THE WIRELESS EQUIPMENT AT THE TOP]

Relief has been brought in this way to vessels in distress and many lives saved. An important example is that of the sinking of the t.i.tanic in 1912. By means of wireless messages from ship to ship the width of the Pacific has been practically covered, as ships en route from America to Australia or Asia can be kept in touch with Honolulu through almost the entire journey. A law in the United States now requires that all ocean pa.s.sage-steamers carrying fifty or more pa.s.sengers on routes of 200 miles or over must be equipped with efficient wireless apparatus and operators. The distance reached must be at least 100 miles. The Canadian law provides that every sea-going and coasting pa.s.senger ship of over 400 tons gross, registered in Canada, and every sea-going and coasting freight ship of over 1,200 tons gross, shall be equipped with a wireless apparatus. Wireless messages have been successfully sent from aeroplanes, balloons and submarine vessels, and the naval vessels of all nations are kept in easy communication by this method. Wireless press messages between America and Europe are also matters of daily performances.

What is Forestry Work?

A Division of Forestry was organized in the Department of Agriculture, some years ago, and the most earnest efforts are being made to prevent any needless waste of our timber lands.

The usefulness of forests to man lies: (1) In furnishing him with timber for building, manufacturing, fuel, etc., and with various other useful products of trees. (2) In their influence on climate. (3) In their influence on water-flow, by keeping the ground more moist, making the outflow more regular, checking the rapid melting of snow, and keeping the hillsides from being denuded of their soil, thus setting up streams and covering cultivated valley lands. The necessity of a proper preservation of the forests seems highly evident, but the nations have been slow in waking up to this fact. Several of the countries of Europe have been largely stripped of their woodlands by indiscreet cutting in the poorest countries, and only recently have the nations been roused to the necessity of their conservation. This is now being carefully attended to in several countries, especially Germany. In China broad mountain regions have been stripped of their trees, with the result that this soil has been swept away by the rains, leaving the rocks bare, while broad reaches of formerly fertile lowlands have been made sterile by the material spread over them by the rains that swept the mountain slopes.

In the United States the broad original forests have been very largely cut away, and those remaining have of late years been so largely reduced by indiscriminate cutting and the ravages of carelessly kindled fires that great alarm is felt as to the future of the lumber supply. Within recent years vigorous efforts have been made to overcome this growing evil. The American Forestry a.s.sociation, founded in 1882, its purpose being the conservative use of our forest resources, has now over 5,000 members, residents of every state, and of Canada and foreign countries.

The first State Forest Commission was organized by New York in 1885 and has now a very large forest reserve set aside in the Adirondacks.

Pennsylvania has also large forest reserves in its mountain districts, and many other states have taken similar action. The art of forestry is also being taught in the schools, and a large body of skilled foresters are now in the service of the states and the general government. In the new and active movement for the conservation of national resources the preservation of the public forests ranks high, and to aid in this purpose the government has withdrawn as national forest areas a vast amount of the public lands, amounting at the present time to 192,931,197 acres, an area about equal to that of Texas and Ohio combined. These woodlands are under the charge of the National Forest Service and cared for by about 3,000 men, of whom 250 are professional foresters. The trees in these forests are cut with careful discrimination, and new trees are planted to take their place, there being forest nurseries containing about 20,000,000 plants and capable of supplying 18,000,000 a year. New York has 1,600,000 acres in its forest reserve, Pennsylvania over 920,000, and the reserves of the other states amount to a very considerable area.

[Ill.u.s.tration: FOREST SERVICE--A LOOKOUT STATION]

[Ill.u.s.tration]

How did the Fashion of Wearing Cravats Commence?

Cravats get their name from the French "cravate," meaning a croat, because this piece of dress was adopted in the eleventh century from the Croats who entered the French service. Towards the end of the eighteenth and the beginning of the nineteenth century the cravat attained an incredible degree of extravagance, but common sense at last brought in the simpler style of neckties that has since prevailed.

How does the Gas Meter Measure Your Gas?

The quant.i.ty of gas used by each consumer is measured by an instrument called a meter, of which there are two cla.s.ses--the wet and the dry.

The wet meter is composed of an outer box about three-fifths filled with water. Within this is a revolving four-chambered drum, each chamber being capable of containing a definite quant.i.ty of gas, which is admitted through a pipe in the center of the meter, and, owing to the arrangement of the part.i.tions of the chambers, causes the drum to maintain a constant revolution. This sets in motion a train of wheels carrying the hands over the dials which mark the quant.i.ty of gas consumed.

The dry meter consists of two or three chambers, each divided by a flexible part.i.tion or diaphragm, by the motion of which the capacity on one side is diminished while that on the other is increased. By means of slide valves, like those of a steam engine, worked by the movement of the diaphragms, the gas to be measured pa.s.ses alternately in and out of each s.p.a.ce. The contractions and expansions set in motion the clockwork which marks the rate of consumption. The diaphragms in all the chambers are so connected that they move in concert.

What is a Game Preserve?

Game preserves have only been introduced comparatively recently in the United States, for the hunting grounds have been freely open to the hunter, but they have been common in Britain and other countries of Europe for centuries.

Their purpose here is the preservation and increase of wild animals instead of their destruction.

Deer parks have long been kept in this country, but the first systematic attempt to foster wild game was made about 1860 by Judge J. D. Caton in a park of Ottawa, Ill.

Chief among those that followed on a large scale is the great game park of Austin Corbin, near Newport, N. H., an enclosure of 36,000 acres, in which a wire fence eight feet high encloses an oblong tract twelve by five miles, through which pa.s.ses a mountain range 3,000 feet high.

American game of all kinds are kept here, from buffalo, elk, and moose to the smaller and more timid varieties, and there has been a rapid increase.

Dr. J. Seward Webb has a 9,000-acre preserve in the Adirondacks, and various other large parks have been established elsewhere, in which our fast-disappearing game animals are augmenting in numbers and game birds of foreign origin have been introduced.

The Story of the Building of a Silo[17]

What is a Silo?

A silo is a place or receptacle for storing green feed to preserve it for future feeding on the farm. In this way green fodder, such as corn and similar crops, are preserved in a green state to be fed in the winter or next summer during an extremely dry season. The silo has the same relation to cattle feed as the gla.s.s fruit jar that mother uses has to the food she preserves in it.

The First Silo.

Silos have been used since very early times in one form or the other, and probably the first we have ever heard of are traceable back in ancient history to the Syrians, who had pits in the ground for the storage of animal feed. These pits have been used in various parts of the Old World ever since and have also been used in the United States.

The pit does not give the best results.

In order to overcome these defects we soon began to see silos erected above ground. Cement, brick, tile and wood were used as building material, with various results. The industry developed rapidly and soon demonstrated what was necessary to keep the silage pure, sweet, clean and succulent. Science and research have helped, until now we can produce silos that will keep this green fodder in a sweet and succulent state until the owner is ready to use it.

What is Put in the Silo?

The princ.i.p.al silage crop is corn, but in different parts of the country there are other crops which can be used to great advantage as subst.i.tutes for corn. Among these are kaffir corn, sorghum, alfalfa, clover, millet, cowpeas, soy-beans, sugar beets, oats and even weeds and thistles. All of these make good silage when properly harvested and stored. Any green fodder can be mixed with the above to make quant.i.ty and secure good results. The main point to be remembered is that the crops to be put away in the silo must contain a certain percentage of sugar and starch in every combination.

Elements of Success or Failure.

There are several things to be remembered by farmers when putting fodder into the silo, if they want to have perfect silage to take out. One of the main things is to see that the silage is cut to proper lengths, which would be about half-inch or one-inch pieces. It should also be well packed, especially next to the wall of the silo. It should have a certain amount of moisture, which it naturally would have if put in at maturity. Good silage is a result of proper cutting, proper packing and a correct amount of moisture, because when the silage is stored it begins to ferment. Heat is generated in the process of fermentation. If the heat is lost through the silo wall, the fermentation is not correct.

If the silage is not packed properly and tightly, especially next to the wall, it does not settle in a compact ma.s.s and air is admitted that spoils the silage; or if the silo wall is porous this is apt to occur.

All these things must be guarded against or a great loss to the owner is probable.

[Ill.u.s.tration: A MODERN REDWOOD SILO WITH STEEL DOME ROOF]

The Story of the Advance of Electricity[18]