T has taken a long time for the hydraulic cartridge to make its way, as a substitute for explosives, in the coal fields of England, but there are indications that it is now coming into general use and that ere long this scientific method of loosening coal, rock, etc., with greater safety to surrounding structures and workmen will be permanently adopted. Briefly put, the system is that of hydraulic pressure, by which

obtainable by this manner of doing the work.

The hydraulic mining cartridge, which has been chiefly designed to supply the need for a different method of bringing down coal after it has been undercut, has many advantages over the high explosives used in the getting of coal.. Obviously, its greatest feature lies in its absolute immunity from danger. By its use coal can be brought down at all hours of

great power may be gradually attained. by means of a tube filled with water. The hydraulic cartridge in its present form is the invention of the late Mr. James Tonge, a British mechanical engineer, who first called a sceptical world's attention to its undoubted merits as far back as 1898. Since that time, however, many improvements have been effected on the original apparatus. Thus the pistons are now made telescopic an inner working within an outer-and the old lever-operated pump (which was such a feature of the original invention) has been replaced by a screw pump, which obtains a greater pressure on the water, as much as six tons to the square inch being

the day, thus avoiding night work for such a purpose. There is no shaking of the roof or damage to doors from vibration of air through fast shots; there is practically no dust or loss of time through missed shots, and an entire absence of noxious fumes.

So effectually does the hydraulic cartridge do its work that in a seam using fine cartridges 450 tons of coal are produced per day, of which 75 per cent is large coal and 25 per cent small. If in the same seam the coal is brought down by explosives, the percentage of large coal invariably decreases to about 65 per cent, whilst the percentage of small coal increases to about 35 per cent. It is claimed that an extra price

hole with the "L" shaped end innermost. The cartridge, with pump and pipe attached is then placed on top of the liner, and both are pushed to the back of the hole. The water tank is filled and hung on the pipe, the stop-cock beneath the water tank opened, and the suction hose coupled, the normal position of the screw handle and pump plunger being assured by pushing the pump plunger in as far as possible, and then unscrewing the large screw handle until it meets the head of the pump plunger. The release valve on the upper left side of the pump is then opened, and the pump plunger slowly drawn back, and rapidly forced inward, three or four times, until a full stream of water, free from air, is ejected from the drain pipe. Then, when the pump plunger is in, the release

begin to crack, until long seams and splits appear in all directions. The maximum pressure is obtained at the moment the elastic limit of the coal is reached, and shortly thereafter it falls in large lumps, rarely too large for one man to handle, and free from powder fracture or slack. The release valve is then opened, and the pistons are pressed back into place, the water returning to the tank through the drain pipe. Should the coal be only broken loose but not down, with the first hole, and it is desired to place the cartridge in the second hole, the pistons may be returned to place by opening the release valve, permitting the water to escape, and then rapidly working the cartridge up and down in the hole. As soon as the pistons are in position, the cartridge is ready for the

Fifteen or sixteen years ago when Mr. Tonge first introduced the hydraulic cartridge quite a number of "safety explosives" were on the market, some of which were more curious than practicable. One of these was a water cartridge, which was named after its inventor, Mr. J. J. Speakman, and which, it was claimed, could be fired without flame and its attendant risk. The outer case of the Speakman cartridge consisted of a tin tube 13 inches long by 134 inches in diameter, sufficiently rigid to prevent crushing down during the operation of fixing and tamping. The tin tube was filled with water and the charge of explosive, which was placed in the water, was partially suspended over the bottom

of the tube by means of an electric wire which connected the detonator in the charge with the battery used for firing, the wire passing out through one end of the tube. When the tube had been filled with water and the charge of explosive placed in position, the open end was securely closed by means of a bung. The cartridge was then placed in the shot hole and tamped in the ordinary way. The charge of explosive when in the cartridge lay in such a position as to be almost completely surrounded by water and by thus placing the charge on the bottom of the cartridge there was a much greater head of water for extinguishing any flame that might arise when the charge exploded.

FURNISHING A TOWN WITH

SHADE TREES

THE town of Farmington, Maine, has a most novel plan for furnishing the village with shade trees. Various people, whether residents of the town or not, set out the trees and maintain them.

This was brought about in this way. In 1885 the village suffered a severe fire, the principal business blocks being wiped out, together with a large part of the residential section and the beautiful shade trees that had been growing for years. The town couldn't afford to replace these trees, so some one devised the scheme of letting people interested in the town contribute towards setting out new ones.

ALL TREES ARE NUMBERED IN FARMINGTON.

To stimulate an interest in the maintenance of these trees, it was decided that each person giving a tree should have his name placed upon it in big letters. This worked like a charm and people from all over the State responded, among them being Ex-Governor Dingley of Lewiston and other prominent men. These signs beginning to be pretty thick and the boys using them for targets, finally a plan was made of the trees with their location,

and each tree was allotted a number on the plan, with the name of its sponsor. As a result of this scheme Farmington now bears the distinction of having the most beautiful shade trees of any town in the State of Maine.

MOVING DAY IN JAPAN.

MOVING DAY IN JAPAN

MOVING day has no terrors for a

man of the people in the land of the Japs. The head of the house picks up the screens, and the wife carries the table and broom and the "Japanese" lantern. That is all there is to it.

MAKING ROADS IN

WASHINGTON

ROAD-MAKING in the state of Washington, especially in the heavily timbered sections, is no sinecure. It takes real men, a lot of hard work, and no little thinking to put a road through in many places where roads are not only wanted, but badly needed.

The automobile is responsible in this state for much of the new undertakings, and there are many miles of fine highway for automobiling in the state. Still, with all that has been done and is now being done, it will be a long time before some of the more remote localities are

satisfactorily opened up. The state has taken a great interest in road building, and is lending its aid in every way possible, not only to get new roads, but to help in maintaining in faultless form those that are now in use.

In building roads through the fir forests the great friend of man is the traction engine and giant powder. After the trees are felled the engine comes in handy in pulling stumps that have been loosened by charges of powder and in dragging off the logs and underbrush.

Logging camps have helped wonderfully in adding to road mileage of the state. The loggers are compelled to build roads as they work into the forests to

take out timber for the mills, and afterward by a little work and expense these trails are transformed into really serviceable. roads.

Four large quarries, fully equipped with stone. crushing machinery, have been opened by the state and are manned by convicts from the state penitentiary. These quarries furnish road building material for state roads.