The Home Medical Library Volume V Part 2

_Laws Regulating Appropriation of Water_

Persons contemplating the establishment of a system of water supply in the country should bear in mind that the taking of water for supply purposes is, in nearly all States, hemmed in by legal restrictions.

The law makes a distinction between subterranean waters, surface waters flowing in a well-defined channel and within definite banks, and surface waters merely spread over the ground or acc.u.mulated in natural depressions, pools, or in swamps. There are separate and distinct laws governing each kind of water. It is advisable, where a water-supply problem presents itself, to look up these laws, or to consult a lawyer well versed in the law of water courses.

If it is the intention to take water from a lake, the property owner should make sure that he owns the right to take such water, and that the deed of his property does not read "to high-water mark only." The owner of a property not ab.u.t.ting on a lake has no legal right to abstract some of the water from the lake by building an infiltration gallery, or a vertical well of large diameter intended for the same purpose. On the other hand, an owner may take subterranean water by driving or digging a well on his own property, and it does not matter, from the law's point of view, whether by so doing he intercepts partly or wholly the flow of water in a neighboring well. But, if it can be shown that the subterranean water flows in a well-defined channel, he is not permitted to do this. The water from a stream cannot be appropriated or diverted for supply or irrigation purposes by a single property holder without the consent of the other riparian owners, and without compensation to them.

CHAPTER II

=Appliances for Distributing Water=

We have so far discussed only the various sources of potable water. We must now turn our attention to the mechanical means for making it available for use, which comprise appliances for lifting, storing, conveying, distributing, and purifying the water.

The location of the source of supply with reference to the buildings and grounds decides generally the question whether a gravity supply is feasible or whether water must be pumped. The former is desirable because its operating expenses are almost nothing, but it is not always cheapest in first cost. Rather than have a very long line of conduit, it may be cheaper to pump water, particularly if wind or water power, costing nothing, can be used.

_Machines for Pumping_

When it becomes necessary to pump water, there are numerous machines from which to choose; only the more important ones will be considered.

We may use pumps operated by manual labor, those run by animal power, pumping machinery using the power of the wind or that of falling or running water; then there are hot-air, steam, and electric pumps, besides several forms of internal-combustion engines, such as gas, gasoline, and oil engines. Each has advantages in certain locations and under certain conditions.

Of appliances utilizing the forces of Nature, perhaps the simplest efficient machine is the hydraulic ram. While other machines for lifting water are composed of two parts, namely, a motor and a pump, the ram combines both in one apparatus. It is a self-acting pump of the impulse type, in which force is suddenly applied and discontinued, these periodical applications resulting in the lifting of water.

Single-acting rams pump the water which operates them; double-acting rams utilize an impure supply to lift a pure supply from a different source.

The advantages of the ram are: it works continuously, day and night, summer and winter, with but very little attendance; no lubrication is required, repairs are few, the first cost of installation is small.

Frost protection, however, is essential. The disadvantages are that a ram can be used only where a large volume of water is available. The correct setting up is important, also the proper proportioning in size and length of drive and discharge pipes. The continual jarring tends to strain the pipes, joints, and valves; hence, heavy piping and fittings are necessary. A ram of the improved type raises water from twenty-five to thirty feet for every foot of fall in the drive pipe, and its efficiency is from seventy to eighty per cent.

Running water is a most convenient and cheap power, which is often utilized in water wheels and turbines. These supply power to run a pump; the water to be raised may come from any source, and the pump may be placed at some distance from the water wheel. Where sufficient fall is available--at least three feet--the overshot wheel is used. In California and some other Western States an impulse water wheel is much used, which is especially adapted to high heads.

_Windmills Used for Driving Pumps_

The power of the wind applied to a windmill is much used for driving pumps. It is a long step forward from the ancient and picturesque Dutch form of windmill, consisting of only four arms with cloth sails, to the modern improved forms of wheels constructed in wood and in iron, with a large number of impulse blades, and provided with devices regulating the speed, turning the wheel out of the wind during a gale, and stopping it automatically when the storage tank is filled. The useful power developed by windmills when pumping water in a moderate wind, say of sixteen miles an hour velocity, is not very high, ranging from one twenty-fifth horse-power for an eight and one-half foot wheel to one and one-half horse-power for a twenty-five foot wheel. The claims of some makers of windmills as to the power developed should be accepted with caution.

The chief advantage is that, like a ram, the windmill may work night and day, with but slight attention to lubrication, so long as the wind blows. But there are also drawbacks; it requires very large storage tanks to provide for periods of calm; the wheel must be placed sufficiently exposed to receive the full wind force, either on a tower or on a high hill, and usually this is not the best place to find water. Besides, a windmill tower, at least the modern one, is not an ornamental feature in the landscape. It is expensive when built sufficiently strong to withstand severe winter gales. During the hot months of the year, when the farmer, the gardener, and the coachman require most water, the wind is apt to fail entirely for days in succession.

_The Use of Engines_

If water is not available, and wind is considered too unreliable, pumping must be accomplished by using an engine which, no matter of what form or type, derives its energy from the combustion of fuel, be the same coal, wood, charcoal, petroleum or kerosene, gas, gasoline, or naphtha. The use of such pumping engines implies a constant expense for fuel, operation, maintenance, and repairs. In some modern forms of engines this expense is small, notably so in the oil engine, and also in the gasoline engine; hence these types have become favorites.

_Advantages of Pumping Engines_

An advantage common to all pumping engines is that they can be run at any time, not like the windmill, which does not operate in a light breeze, nor like the ram, which fails when the brook runs low.

Domestic pumping engines are built as simple as possible, so that the gardener, a farm hand, or the domestic help may run them. Skill is not required to operate them, and they are constructed so as to be safe, provided ordinary intelligence is applied.

In using a fuel engine it is desirable, because of the attendance required, to take a machine of such capacity and size that the water supply required for two or three days may be pumped to the storage tank in a few hours.

_Expansive Force of Heated Air Utilized_

A favorite and extensively used type of domestic pump is the hot-air engine, in which the expansive force of heated air is used to do useful work. Among the types are simple and safe machines which do not easily get out of order. They are started by hand by giving the fly wheel one or more revolutions. If properly taken care of they are durable and do not require expensive repairs.

_Gas and Gasoline Engines_

In gas engines power is derived from the explosion of a mixture of gas and air. Where a gas supply is available, such engines are very convenient, for, once started, they will run for hours without attention. They are economical in the consumption of gas, and give trouble only where the quality of gas varies.

Owing to the unavailability of gas on the farm and in country houses, two other forms of pumping engines have been devised which are becoming exceedingly popular. One is the gasoline, the other is the oil engine. Both resemble the gas engine, but differ from it in using a liquid fuel which is volatilized by a sprayer. Gasoline engines are now brought to a high state of perfection.

_Kerosene or Crude Oil as Fuel_

In recent years, internal-combustion engines which use heavy kerosene or crude oil as fuel have been introduced. These have two palpable advantages: first, they are safer than gasoline engines; second, they cost less to run, for crude oil and even refined kerosene are much cheaper than gasoline. Oil engines resemble the gas and gasoline engines, but they have larger cylinders, because the mean effective pressure evolved from the explosion is much less than that of the gasoline engines.

Oil engines for pumping water are particularly suitable in regions where coal and wood cannot be obtained except at exorbitant cost.

Usually, the engine is so built as to be adapted for other farm work.

It shares this advantage with the gasoline engine. Oil engines are simple, reliable, almost automatic, compact, and reasonable in first cost and in cost of repairs. There are many forms of such engines in the market. To be successful from a commercial point of view, an oil engine should be so designed and built that any unskilled attendant can run, adjust, and clean it. The cost of operating them, at eight cents per gallon for kerosene, is only one cent per hour per horse-power; or one-half of this when ordinary crude oil is used. The only attention required when running is periodical lubrication and occasional replenis.h.i.+ng of the oil reservoir. The noise of the exhaust, common to all engines using an explosive force, can be largely done away with by using a m.u.f.fler or a silencer. The smell of oil from the exhaust likewise forms an objection, but can be overcome by the use of an exhaust washer.

_Steam and Electric Pumps_

The well-known forms of steam-pumping engines need not be considered in detail, because high-pressure steam is not often available in country houses. Where electric current is brought to the building, or generated for lighting purposes, water may be pumped by an electric pump. Electric motors are easy and convenient to run, very clean, but so far not very economical. Electric pumps may be arranged so as to start and stop entirely automatically. Water may be pumped, where electricity forms the power, either by triplex plunger pumps or by rotary, screw, or centrifugal pumps.

_Pumps Worked by Hand_

s.p.a.ce forbids giving a description of the many simpler devices used for lifting water. In small farmhouses lift and force pumps worked by hand are now introduced, and the old-fas.h.i.+oned, moss-covered draw-bucket, which is neither convenient nor sanitary, is becoming a relic of past times.

_Reservoirs and Storage Tanks_

The water pumped is stored either in small masonry or earth reservoirs, or else in storage tanks of either wood, iron, or steel, placed on a wood or steel tower. Wooden tanks are cheap but unsightly, require frequent renewal of the paint, and give trouble by leaking, freezing, and corrosion of hoops. In recent years elevated tanks are supplanted by pressure tanks. Several such systems, differing but little from one another, are becoming quite well known. In these water is stored under suitable pressure in air-tight tanks, filled partly with water and partly with air.

_A Simple Pressure System_

One system consists of a circular, wrought-steel, closed tank, made air- and water-tight, a force pump for pumping water into the tank, and pipe connections. The tank is placed either horizontally or vertically in the bas.e.m.e.nt or cellar, or else placed outdoors in the ground at a depth below freezing. Water is pumped into the bottom of the tank, whereby its air acquires sufficient pressure to force water to the upper floors.

This simple system has some marked advantages over the outside or the attic tank. In these, water gets warm in summer and freezes in winter.

Vermin and dust get into the tank, and the water stagnates. In the pressure tank, water is kept aerated, cool, and clean.

Another pressure tank has an automatic valve, controlled by a float and connected with suction of pump. It prevents the tank from becoming water-logged by maintaining the correct amount of air inside.