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The "Witch House" 310 Essex St., Salem, Mass., is said to have been owned by Roger Williams, who was teacher of the first church for several months. Tradition relates that the preliminary trials of the witchcraft cases took place here when it was occupied by Jonathan Corwin one of the judges. The interior and chimney are much in the same state as in 1692.

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The former home of Louis John Rudolph Agassiz. Here he lived in his home at Nahant for many years beloved by the fishermen and village folks. The house is still standing and occupied by his family.

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House of Seven Gables in Salem, Mass., where lived Susan Ingersoll when during a visit of her kinsman, Nathaniel Hawthorne, she took him up into the attic and showed him the Seven Gables, which suggested the book of that name.

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Page House in Danvers built in 1743. The old deeds are still preserved in the house. Here at one time Gen. Cage had his headquarters, and it was here that during the time the duty on tea was imposed, and tea was a forbidden luxury, that Mrs. Page, who was a tory at heart, drank her tea with friends upon the roof.

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THE machinery in a power plant Boilers are placed in brickwork, to prevent is required to furnish power for

loss of heat from radiation from the furnace,

and to guide the hot gases.
so many different purposes and
under such varied conditions,

The Chimney that, even for a given rating, it varies

After giving up a part of their heat to the considerably. Many factors must be con- water, the hot gases are conducted to the sidered in selecting the boilers and en chimney, from which they escape into the at

mosphere. The chimney also aids the draft. gines and their accessories.

Draft is dependent upon the difference in

weight of the cool air (atmosphere) and the Location of Plant

heated gases in the chimney. Therefore, in The leading points to be considered under general, the higher the chimney, the greater this head are: (1) Cost of delivering coal to the draft. From 100 to 250 feet is the usual boilers; (2) Method of transmitting power; and (3) Cost of water for condensing. As the handling of coal and ashes may be an im

The Engines portant part of the running expenses, the plant It is the duty of the engines to transform should be located near a railroad; and in the heat energy in the steam into power. Steam large plants, conveying machinery is often in- is admitted to each side of the piston alterstalled. The value of a nearby natural water nately, driving it back and forth in the cylsupply is apparent when one considers that inder. This back-and-forth motion is con15 to 20 per cent of the fuel can be saved by verted into rotary motion by the connecting condensing the exhaust steam from the en- rod and crank. There are innumerable makes gines. The quantity required is considerable, and types; but after the service is determined, for over 400 pounds is usually necessary per an engine can be selected to do the work ecohorse-power per hour.

nomically. The engine is usually placed on a The building should be of brick or other concrete foundation, and so arranged that the fireproof material, and of sufficient size to con- cylinder is near the boiler; this allows a short tain the machinery without cramping. It is main steam pipe. common practice to place a wall between the engines and boilers. The boilers are usually

The Condenser placed on the ground level, and the floor of

In most power plants the exhaust steam the engine room raised a few feet above. If

from the engine is condensed; that is, the the engine is on the ground level, a pit must

latent heat is taken from it by cooling. This be made for the condenser, because this ap

changes it from a gas (vapor) to a liquid. paratus should be below the engine.

The great reduction in volume decreases the Boilers

pressure against which the piston acts, and

consequently reduces the amount of steam supIn the boiler, the heat is transferred from plied to the cylinder. The condenser is merely the fuel to the water. To make the heating a shell containing many small tubes. Cold surface more effective, the hot gases, in the water circulates within these tubes; and, as fire-tube type of boiler, are made to pass the steam strikes the cold surfaces, it is conthrough many small tubes, or, in the water densed. tube type, around water-filled tubes. As to An air-pump sucks the condensed steam economy, the two types are about alike. The (water), and any air that may have been in fire-tube boiler is a reliable generator, and is the steam, from the condenser, and sends the

referred; the water-tube boiler is safer, water to the "hot well.” This well is simply and steam can be raised more rapidly. A a reservoir for storing hot water until it is water-tube boiler is shown here.

delivered to the boiler. (246)

(Rights of Publication Reserved by Author)

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cylinder; an Auxiliary steam pipe, to convey steam to the feed-pump; a feed-pipe, through which the feed goes to the boiler; and piping to connect the air-pumps with the hot well.

This piping, whether for steam or hot water, must be strong (to prevent bursting); as direct as possible; and, for steam, should be well covered, to prevent loss of heat by radiation.

The Feed-Pump As the pressure in the boiler is considerable (usually about 150 pounds per square inch), there must be some means for forcing the feed-water into the boiler. This is usually accomplished by a direct-acting steam pump. This piece of apparatus consists of two cylinders set in line, and a piston in each. As the pistons are fastened to the same rod, steam pressure on one moves the water in contact with the other. By making the steam piston larger than the water piston, the pump will easily force the water into the boiler.

Piping In a large plant there is a confusing network of pipes, but every one is an important part of the system. Some convey water, and some steam. Of these pipes, the principal ones are: (1) the Main steam pipe, which carries the live steam from the boiler to the engine

Circulation Let us assume the water to be in the boiler. After being converted into steam, it passes through the main steam pipe to the engine cylinder, where it drives the piston. After doing its work, it goes to the condenser, where it is condensed to hot water. The water is then pumped to the hot well, from which it is drawn by the feed-pump and is forced into the boiler, there to be evaporated again into steam.

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Quotation Explained A PHYSICIAN, finding a lady reading "Twelfth Night," said: “When Shakespeare wrote about Patience on a monument, did he mean doctors' patients ?"

"No," she answered; "you don't find them on monuments, but under them.”

The Last Straw .. The long-haired caller in the editorial room was indignant. “Poets are born, sir," he said

to the eminently practical editor.

"Of course they are," responded the editor, suavely; "you didn't imagine I thought they were hatched, did you?”

“I mean, sir, they are born; born, sir-do you understand?"

"I think I do," and the editor rubbed his chin reflectively;

"but why are they?” That was the straw that fractured the spinal column of the camel, and the poet stalked out of the den.—Grit.

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Jerry's Care for his Property It has been said of the Southern darkey that he has not always a clear idea as to property rights, but on some points it appears that he is not in the least hazy.

An old colored man in the days "befo' de wah” was given one of his master's cast-off hats, which he wore with great pride. One Sunday his master met him coming home from a campmeeting in a pouring rain, bare-headed and holding his hat under his coat. Later on the master questioned him jocosely:

"Why didn't you wear your hat, Jerry? Did you feel the need of cooling your head ?"

"You see it's like dis, sah," responded Jerry. "My head is yours, but my hat is mine, and nachelly I feels like taking care ob it, sah.”

A Young Financier Oii coming home from church on Sunday Archie's mother asked him how he liked it, and Archie said it was fine.

“What do you like most in the church?” asked his mother.

"Well, the best part is where they pass around the money," and turning to his father, said: "How much did you get? I got a dime."

Collars and Cuffs AFFECTED YOUTH_“You can always tell a gentleman, don't you know, by his collars and cuffs. I am always particular about that.”

OLD GENTLEMAN-“Yes, and if I were your father I should be particular to see that you were properly collared and cuffed.”

Settled out of Court "It is a great pity," said the judge, “that old friends, as you seem to have been, should appear before me in such a way. Surely this is a case which might be settled out of court?"

"It can't be done, judge,” answered the plaintiff, moodily. "I thought of that myself, but the cur won't fight.”—Boston Herald.

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