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Stirling Water Tube Boiler.

Q. How is a water tube boiler constructed?

A. The Stirling Water Tube Boiler as illustrated, has three upper or steam domes, the steam space of all of which is connected, while the water space of the two front domes is connected. All of these three domes are connected with a lower or mud drum, which is not bricked in, but is left free to expand and contract.

The three upper domes are supported on wrought iron beams, which are entirely free and independent from the brick work. The feed water enters the rear upper dome, and descends gradually to the lower or mud drum, being heated in its descent by the escaping gases to a sufficiently high degree to cause precipitation in the mud drum of all of the solid or scale bearing matter that the feed water contains. The water then in the front bank of tubes is chemically pure, and all danger of scale reduced to a minimum.

Q. What advantages have the water tube boilers?

A. One of the great advantages of this style of boilers is its distinct circulation, being up the front bank of tubes across from the front upper dome to the middle dome, down the middle bank of tubes to the lower or mud drum, and up again the front bank of tubes, and so on in circuit. It also has great steaming capacity, and is economical in fuel. Steam is taken from the middle dome.

This marked circulation is a desideratum in boiler practice, and the Stirling may be said to be the first that has accomplished it to so great a degree.

Q. What disadvantages have the water tube boilers?

A. Expensive first cost of setting them up in brick work.

J. I. Case Traction Engine.

J. I. CASE TRACTION ENGINE.

This engine is known as the Center Crank, Rear Gear traction. The engine is mounted on the center of boiler at the rear end, and rests upon and is securely bolted to two saddles. The rear saddle also supports the two outer bearings for the crank shaft.

The engine frame is cast in one piece, cylindrical in shape, with bored guides for cross-head, and has large lateral openings. It forms the front cylinder head at one end, and contains the two pillow block bearings at the other.

The cylinder is overhanging and self-lining.

It has the locomotive type boiler, with open bottom fire box, covered with an ash pan, and has a steam dome at front end. The outer shell of this boiler over fire box extends beyond the back head. To this extension is bolted the two brackets containing the bearings for the main axle and cross shaft.

The traction wheels are of the wrought rim steel spoke type, with high mud cleats bolted diagonally across the entire width of tire.

The front axle is supplied with a ball-bearing bolster, which supports the front end of boiler. The engine has the Friction Clutch, Link Reverse Gear, Long Heater, Independent Pump, Injector, Water Tank on side, Foot Board with Tool Boxes attached, and all necessary attachments and fittings to make a complete traction engine, and one that will be perfectly safe with proper handling.

The steering wheel and band wheel are on the same side of engine, and the straight stack and extension front has a spark arrester on the inside.

This engine is constructed to burn either coal or wood and with special arrangement can be made to burn straw.

J. I. CASE RETURN FLUE TRACTION ENGINE.

The foregoing description of the J. I. Case Traction Engine will apply to this engine in every particular with the exception of the boiler, the construction of engine, the traction gear and fittings being exactly the same.

The boiler however is of the return flue, straw-burner type It is supplied with a large steam dome on front end and also a mud drum on under side. The fire box is at the rear end of main flue, and is covered by an ash pan. The boiler is lagged and jacketed, and the stack has a screen spark arrester at the top. This engine is intended to burn straw, but it will burn either wood or coal equally well, and is said to be very economical in fuel.

J. I. Case Return Flue Traction Engine.