draft, the air to supply the fans being taken out of each of the three ash-bins over the hot clinkers, into 20-inch vitrified pipe, then into an air chamber 3 x 6 feet, then through the fans into two galvanized air-tight ducts, under the furnaces. Air is also taken out of the garbage bin through a 20-inch galvanized pipe through the fans and into the ducts.

Under each furnace and directly under the grates are three holes 12 inches in diameter in the ducts. Two of these holes supply air to the side grates and one to the fire-box, the supply of air being regulated by dampers over each hole. The dampers are located in the air pipes proper, and the fans are so connected that they can draw from the ash-pits, combustion chambers and garbage bins, or separately, and can be operated singly or together. The gases from the furnaces pass through a large combustion chamber where a temperature of about 1,200 degrees is maintained. Dead animals can be incinerated in this chamber. The chamber is connected to the 125-foot chimney, and it has been found that all gases and bad odors disappear before reaching the top of the chimney.

In connection with the operation of the plant a 280-gallon tank is provided for hot water, which is supplied through 2-inch pipe placed in the combustion chamber. This hot water furnishes two radiators in the office and toilet rooms and also furnishes hot water on the tipping floor and the firing floor for cleaning purposes.

The building was constructed by local contractors, and the furnaces were con

structed by the Burke Furnace Company, of Chicago. The plant is being operated by the Department of Streets and Sewers, Clinton H. Fiske, Director.

The guarantee made by the Chicago Incinerator Company for this plant was that it would incinerate 80 tons of garbage in 24 hours without any nuisance or bad odors; that it would use not over 8 kilowatts of electricity for the forced draft fans per ton of garbage; that it would not use more than 6 per cent, or 120 pounds, of coal per ton of garbage. Tests show that this capacity has been raised to at least 100 tons per 24 hours and that it requires less than I kilowatt of electricity for each ton of garbage and less than 100 pounds of coal per ton of garbage. The plant is being operated 24 hours a day in three 8-hour shifts and requires three men on the firing floor, three on the charging floor, and a foreman for each 8-hour shift. It is incinerating garbage without any offensive odors or smoke for about $1 a ton, showing a saving of $1.10 a ton over the contract for dumping it onto barges at $2.10. It is the intention of the city to erect other plants as soon as possible, thus eliminating the long haul to this one plant and to further reduce the cost of collection. The plant has been in operation for over six months and as yet no complaint has been made against this method of disposal of garbage. The Department believes that after 84 years of garbage disposal troubles the city has found the proper solution of its garbage disposal problem in the incineration of the putrescible wastes of the city.

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HE first water system in Joplin, Mo., was the old-fashioned tank water wagon operated by S. E. Eells, who lived in East Joplin. He furnished the city supply from a deep well at his home. Families who had not built cisterns when they erected their mining cabins, bought water and kept it in barrels.

The water wagon traveled over its route each day. The housewife who needed water put a white rag on a stick and hung

it above her water barrel. Water bills were run by the month or week, and when the water hauler left either a barrel or a half-barrel of water, he made a mark on the side of the barrel with a pencil. By counting the marks and figuring it at 10 cents a barrel, the patron of the water man computed his monthly bill. When the town began to assume larger proportions, water was also hauled from the mining pumps. -Joplin Globe.

It will be noticed that the solution of this formula requires subtraction, division and multiplication. For checking flow meters, extreme accuracy is necessary, as results must often be carried out to as many as ten decimal places.

Profit and Loss Showing Percentages

is reproduced above. In the extreme righthand column are percentages carried out to six places. This statement and others used by the Kansas City Municipal Plant follow in the main the standard accounting plan of the National Electric Light Association, which is used by the majority of power companies and departments in the United

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HE forms of meter rates now in general use in American cities may be classified as follows:

Uniform Minimum Rate.-A minimum rate is an amount that is collected, no matter how small the consumption may be. This is the plan now used in Detroit, where he charge is $1 per quarter. This charge entitles the user to 1,000 cubic feet, but the charge is made for any quantity under that amount. The minimum rate charge is used in the majority of American cities and may be used in connection with a uniform rate or any one form of sliding or step rate.

Service Charge. This is a charge made in addition to a charge for water. It increases with the size of the meter or service connection. Its use in American cities is increasing. This is the system that has been recommended for adoption by the New England Water Works Association.

Graduated Minimum Rate.--In this form of rate the minimum charge increases with the size of the meter, as in Philadelphia, where the minimum charge for a 8-inch meter is $12 per year, and for a 6-inch meter $1,150 per year.

Sliding Scale.-This scale may be used with or without the minimum rate or service charge and includes all cases where a varying rate is charged according to the quantity of water used. This plan, with a minimum charge, is now used in Detroit

and in the majority of American cities. The type of sliding scale generally used provides that the water used to a certain limit is charged at a certain rate and additional quantities are charged a lower rate, but the higher charge on the first quantity remains a part of the bill.

Other Forms of Rate.-Several other forms of rates have been used to a limited extent.

The uniform rate is the rate in which the cost of water, either per gallon or per cubic foot, is the same to the small consumer as to the large consumer and is the same whether the quantity furnished is little or much. This method is much used.

The jump scale provides that a certain quantity of water is charged for at a certain price; beyond that limit and inside another limit a lower price is named. By this method it is possible to get a lower bill by drawing an additional quantity of water; as, for instance, if 1,000 cubic feet were charged for under this system at the rate of $1 and all amounts beyond that at the rate of 50 cents per 1,000 cubic feet, the consumer, by wasting his water so he exceeded the 1,000 cubic feet limit, say 1,100 cubic feet, would be billed at 50 cents per thousand.

With the logarithmic scale, the amount of water bill is found by multiplying a quantity of water, raised to some power less than I by a constant.

A very large share of the money obtained to improve the highways throughout the state of Minnesota in accordance with the terms of the constitutional amendment comes from the automobile owners of Minneapolis and St. Paul, says the Minneapolis Tribune. It is a pleasant and significant thing to

chronicle that very few complaints come from the motorists of the two big cities about the taxes they are required to pay into the good roads fund, although they are well aware that little of this money, if any, is used for direct, close-range benefit of the cities Urban taxpayers take care of their own streets and boulevards in the usual way.