Making Water Pump Itself
DOES water seek its own level? Yes, with an if—if the water is the same density throughout. If the density of water in two connecting vessels differs, the level of the lighter water will be higher.
There are different ways in which density can be affected. One is by heat; another is by adding to the water something that is lighter than itself—air, for instance. This can be shown in a very simple way with a tea-kettle and a short tube. Fill the kettle with water and insert the tube in its spout until it nearly touches the bottom of the spout. Then blow bubbles into the spout through the tube. The bubbles will mix with the water in the spout and lighten it. The solid water in the kettle will then overbalance the lighter aerated water in the spout; the heavier water in the kettle will force its way into the spout in an endeavor to establish equilibrium, and the spout will overflow. The water will continue to flow from the spout until the water level in the kettle becomes so low that equilibrium is established. Then the flow will cease. It is apparent that the force of the air has little to do with the action, for the air is blowing against the direction of flow of the water. The water really pumps itself.
Keeping the case of the kettle in mind, we will now see how it suffices to illustrate the principle of the air-lift. One or more wells are sunk to a depth considerably below the level of the underground water. A pipe of large diameter open at the bottom is then sunk nearly to the bottom of each well. This is for the water discharge. When not pumping, the water in this pipe will be at the same level as that in the well. A second pipe of small diameter is also sunk to the bottom of each well, terminating in a chamber which surrounds the water-pipe. Air passes from this chamber through small perforations into the water-pipe, mixing small bubbles with the water, giving a “champagne effect.” These bubbles rise very slowly, until they are distributed throughout the entire column of water in the discharge pipe. Coincident with the admission of air, the column of water elongates until it discharges.
The weight of water in the well over-
balances the very much longer column of aerated water in the pipe. Thus the well-water flows into the discharge pipe, is aerated and in turn discharged.
The air pressure must be greater than the water pressure at the bottom of the well. Otherwise the water would force its way into the air-pipe and stop operations.
The water may be lifted vertically into a tank or reservoir or may be discharged into a “booster” and then carried horizontally. The booster is simply a vessel which permits the air and water to separate.
In the air-lift system there are absolutely no working parts, such as pistons, valves, etc., under ground, which are liable to wear, to rust, or to become defective with use. Air is supplied by an air-compressor, which may be located far from the wells, if desired.
A “Jackomobile” for Two
THE illustration shows a combination of the oldest and newest means of transportation. In 1904 it was a new automobile, but in subsequent years it fared so hard at the hands of one owner after another that its engine was
discarded and the machine itself was on the way to the dump heap when two boys assumed ownership. They obtained a burro and after fitting the body of the old model with shafts, went about their Michigan town with the only “Jackomobile” extant.
The Milk-Can Trolley
FOR the rapid and economic handling of milk a Western creamery has installed an aerial tramway, six hundred
feet long, leading from its milking barns direct to the refrigerating and bottling plants. The milk travels over the top of stables en route, and a complete trip of one five-gallon can on a two-wheeled carrier takes but seventy-five seconds. Formerly this work was done by a driver with team and wagon. The tramway has taken their place.
There are always two cans in transit at the same time, one coming in full and one returning empty. The attaching links are so spaced that when the full can has reached the end of its trip at the bottling house, the empty can has also reached its destination at the milking barn and stops at the proper place, automatically. The drag-cable is driven by a reversible set of small drums having grooves to receive the cable. Signals to start are given from the barn by a magneto bell.
For dairies which handle large quantities of milk and make express shipments to large cities, this conveyor is a great step in advance, since it reduces the time required in handling the milk.
Straw Raincoats of Japan
THERE are as many different kinds of alleged waterproof raiment in existence as there are straws in the grotesque costume of the Japanese in the. accompanying illustration. But there is just one raincoat which lives up to its rainproof claims, and, in fact, has lived up to them for a thousand years and more, and that is the ricestraw combination worn by the Nippon.
In addition to being light, porous and warm in cold, wet weather it serves as a “blind” for the wary fish which can discern no danger lurking in a fishingpole protruding from what appears to be a mere sheath of grass. A Nippon angler seated on a river bank wearing his rice-straw cloak resembles so closely a tuft of rank grass or a growing scrub that the most preyed-upon animals fail to detect danger.
From the score of waterproof materials and impervious clothing there is a new Paris product which is said to be very effective, providing one doesn’t approach too close to the fire. It is highly inflammable on chance ignition, since its inner lining is composed of guncotton sheeting. There is also an English raincoat which weighs but nine pounds when dry, but
which, when worn through rain, will absorb water as readily as a sponge. In an hour it has been known to absorb six pounds of water, adding greatly to its weight and accelerating physical exhaustion. Yes, it’s waterproof.
What? Only Three Kinds of Feet?
A RECENT meeting of foot doctors brought forth the information that all feet are divided into three classes, namely, inflared, outflared and straight— the first two classes being scientific divisions for the common afflictions known as pigeon-toes and bow-legs. One doctor said: “Shoes are proverbially
made to fit the eye and the pocketbook, but not the feet.” In other words the manufacturers have not kept step with the times by making shoes of three classes.
The ordinary classification of boots, shoes and slippers does not fit with the inflared, outflared and straight classes of feet, stated the doctors, as was proved by the fact that most manufacturers ride in automobiles. To remedy the situation it is proposed that all shoes be manufactured to conform with the three general classes of feet, that both feet and shoes may advance side by side in the scale of civilization.