Length and Weight of English Iron Guns.

French Iron Guns, in English Weights, &c.

Ranges of Brass Guns, with one Shot. 1793.

Ranges from Brass Guns, with Two Shot. 1793.

Ranges from Brass Field Guns, with small Charges. 1798.

N. B. The above was a 12 Pr. Medium, and a 6 Pr. Desagulier’s.
The Distances are given in Yards.

N. B. There were three rounds fired at each change, but they were all so nearly alike that it has been thought necessary to put down only one of them.—1802.

Ranges with Sea Service Iron Guns. 1796.

Ranges with 4⅖ Shells from a 12 Pounder, Medium.

Ranges with French Brass Field Guns,
with Round Shot.

The above are in French weights and measures.

GUNPOWDER.—Proportions of the different Ingredients for making Gunpowder, by different Powers in Europe:

Proofs of Powder.—The first examination of powder in the king’s mills, is by rubbing it in the hands to find whether it contains any irregular hard lumps. The second is by blasting 2 drams of each sort on a copper plate, and in this comparing it with an approved powder; in this proof it should not emit any sparks, nor leave any beads or foulness on the copper. It is then compared with an approved powder, in projecting an iron ball of 64 lbs. from an 8 inch mortar, with a charge of 2 ounces. The best cylinder powder generally gives about 180 feet range, and pit 150; but the weakest powder, or powder that has been redried, &c. only from 107 to 117 feet.

The merchants’ powder, before it is received into the king’s service, is tried against powder of the same kind made at the king’s mills; and it is received if it gives a range of ¹/₂₀ less than the king’s powder with which it is compared. In this comparison both sorts are tried on the same day, and at the same time, and under exactly the same circumstances.

The proof of fine grained, or musquet powder, is with a charge of 4 drams from a musquet barrel, to perforate with a steel ball a certain number of ½ inch wet elm boards, placed ¾ inch asunder, and the first 39 feet 10 inches from the barrel: the king’s powder generally passes through 15 or 16, and restoved powder from 9 to 12. The last trial of powder is by exposing about 1 pound of each sort, accurately weighed, to the atmosphere for 17 or 18 days; during which time, if the materials are pure, it will not increase anything material in weight, by attracting moisture from the atmosphere.

In this exposure 100 lbs. of good gunpowder should not absorb more than 12 oz. or somewhat less than one per cent.

Powder Marks.—The different sorts of powder are distinguished by the following marks on the heads of the barrels.

The red L G, F G, or S G, denotes powder entirely made of the cylinder charcoal, and is that which is now always used on service. The white L G being a mixed powder, is not so uniform as the other, and is therefore generally used in filling shells, or for such other purposes as do not require much accuracy. All powder for service is mixed in proportions according to its strength, so as to bring it as much as possible to a mean and uniform force.

French Gunpower.—The French proof ball is of brass, and weighs 60 lbs. French: the diameter of the mortar 7 inches 9 points, or ¾ of a line, and has one line of windage. The chamber holds exactly 3 ounces; and their best powder must give a range of 90 toises, and their restoved powder a range of 80 toises, to be received into the service. But the powder they now make, when new, will give a range of 100 and 120 toises; and Mr. Lombard calculates all his tables from experiments made with powder giving 125 toises with the eprovette.—The above dimensions and weights are all of French standard.

GUN METAL—is composed of 8 or 10 lbs. of tin to 100 lbs of copper.—The largest proportion of tin is used for mortars

H aircloth—Weight 30 lbs.—length 15 feet—breadth 11 feet.

HAND BARROW.—Weight 13 lbs.—length 5 feet 4 inches.

HANDSPIKES.—Common, weight 11 lbs. length 6 feet.

HARNESS.—For men, one set, 26 lbs. length, 12 feet.—Wheel harness for a pair of horses, such as is used in the service of artillery, about 1 cwt.

HORSES.—An allowance of 3 feet is generally made for the breadth of each horse standing at picket; and about 9 feet for the length of a horse.

A light dragoon horse, mounted and accoutered complete, carries about 2 cwt. 1 qr. and 14 lbs. without forage.

Horses in the service of artillery should not be made to draw above 3 cwt. each, besides the weight of the carriage.

Horses for this service should never be lower than 14¾ hands. The contractor is obliged to furnish them of this height for government.—A horse is generally supposed equal to five men.

Military horses walk about 400 yards in 4½ minutes.

Trot the same distance in 2 minutes 3 seconds, and gallop it in about 1 minute.

With great burthens, less weight must be allowed for each horse to draw, than with medium burthens; as it cannot be supposed that, of a team of 8 horses, the leaders can draw so much as the horses nearer the carriage; and this disadvantage must increase as the team lengthens. A team of

It is usual in heavy carriages to reckon all their weight exceeding 12 cwt. as part of the load.

Horses allowed for drawing Field Artillery Carriages.

All the horse artillery carriages are drawn by 4 horses each, except 12 prs. which have 6 each. Park Carriages—12 pr. medium, and 6 pr. heavy, 6 horses each—6 pr. light, and 5½ howitzer, upon the new construction, are allowed each 4 horses, but upon the old only 3 each.

HOWITZERS.—Dimensions and Weight of Brass Howitzers.

French Howitzers, in their own Weights and Measures.

Table containing the Natures of Howitzers
used by different Powers in Europe.

Ranges with a light 5½ inch Howitzer. 1798.

Ranges with a heavy 5½ inch Howitzer. 1793.

L evelling—Table shewing the Difference between the True and Apparent Level.

This table will answer several useful purposes.

First.—To find the height of the apparent level above the true, at any distance.—If the given distance be contained in the table, the correction of level is found in the same line with it; but if the exact distance be not found in the table, then multiply the square of the distance in yards, by 2.57, and divide by 1,000,000, or cut off 6 places on the right, for decimals; the rest are inches: or multiply the square of the distance in miles, by 66 feet 4 inches, and divide by 100.

Second.—To find the extent of the visible horizon, or how far can be seen from any given height, on a horizontal plane, as at sea, &c.—The height of the observer’s eye above the horizon being known, the extent of his visible horizon is found in the column opposite, under the word Distances.

Third.—To find the distance of any object when it first comes in sight, its height being, known.—For the distance of any object will be the extent of the visible horizon of the observer, added to the visible horizon of the point he observes. It is necessary in this case for the observer to know only the height of that part of the object which is kept from his view, by the curvilinear figure of the globe.—Knowing the distance of an object, its height may be found in the same manner.

If the height or distance exceed the limits in the table; then, first, if the distance be given, divide it by 2, 3 or 4, till the quotient comes within the distances in the table; then take out the height answering to the quotient, and multiply it by the square of the divisor for the height required. But when the height is given, divide it by one of these square numbers, 4, 9, 16, 25, &c. till the quotient come within the limits of the table, and multiply the quotient by the square root of the divisor.

LOAD.—Artillery carriages, or waggons, are frequently loaded with 14 cwt. for 3 horses, and 20 cwt. for 4 horses. This, however it may answer on an English road, is a great deal too much for general service. No doubt a carriage of one construction will travel easier than of another, with the same weight; and where the mechanical advantage thus gained is greatest, the heaviest weight may be put, with the same number of horses; but in the carriages usually made for the service of artillery, 4 cwt. per horse, beside the weight of the carriage, is the utmost they ought to be allowed to draw.

The French ammunition waggons, which are drawn by 4 horses, are always charged with 1200 pounds only.

The regulations for home service in 1798 state the load for a bread waggon at 2400 lbs. and for a cart of entrenching tools at 400 lbs. Men used to bear loads, such as porters, will carry from 150 to 250 pounds.

A horse will carry about 300 lbs. and a mule about 250 lbs.—See also the word Horses.

M agazines—The present practice is not to make large powder magazines for batteries, but to disperse the barrels of powder, or cartridges here and there in small magazines, about 6 or 7 fathoms, in the rear of the battery; as it appears better to loose a small quantity from time to time, than to run the risk of the whole being destroyed, by a single shell falling into the magazine. These small magazines or entrenchments, will hold about one or two tons of powder; and are about 8 or 9 feet square. They ought to be well covered from the fire of the place, and always in the rear of one of the merlons. When they cannot be sunk in the ground, they should be secured by sand bags or gabions. They should be made with attention, as should the communication from them to the battery. Two magazines of this kind will be required for a battery of six pieces.

Permanent Powder Magazines.—According to Vauban’s plan, powder magazines are commonly made 10 fathoms long, and 25 feet wide, in the clear. The foundation of the longest sides, is 9 or 10 feet thick, and 6 feet or more deep, according to the nature of the ground. The side walls raised upon these are 8 or nine feet thick; and if there is not to be an upper story, 8 feet will be sufficient height above the foundation. By this means the flooring maybe raised above the ground, free from damp, and there will remain 6 feet from the floor to the spring of the arch. The arch is formed of layers of bricks, arched one over the other, and ought to be 3 feet thick at the top. The exterior surface of the arch terminates with, an angle at top, like a roof; which angle must be of such magnitude as to make a thickness of 8 feet over the key stone of the arch. The foundation at the gable ends is 5 feet thick, and the same depth as the sides; these ends are built up 4 feet thick, from the foundation to the top of the roof. The long sides are supported by counterforts, 6 feet thick and 4 feet long; and placed 12 feet asunder. The ventilators are placed, one in the centre of each space between the counterforts, and are made with a die across them of 1½ feet. These ventilators are also closed with plates of iron. The magazine is lighted by a window in each end, high up, which are opened and shut by means of a ladder. These windows are secured, each by two shutters, made of plank 2 or 3 inches thick; and the outer one covered with sheet iron, and both fastened with strong bolts. The entrance to the is closed by two doors, one of which opens inwards, and the other outwards; the outward one is covered with sheet iron. The entrance of the magazine should, if possible, be placed towards the south. A wall of 1½ feet thick, and 10 feet high, is built round the magazine, at 12 feet distance. A magazine of the above dimensions will contain about 94,800 lbs. of powder, in piles of 3 barrels each; for a greater number piled above each other destroys the barrels, damages the powder, and occasions accidents.

MATCH.—The slow match used by the English is made by contract: one yard of it will burn about 8 hours. The French slow match is usually made by soaking light twisted white rope for three days in a strong lye. It burns about 3 feet in 6 hours.

Slow match was made at Gibraltar, during the last siege, in the following manner: eight ounces of saltpetre were put into a gallon of water, and just made to boil over a slow fire; strong blue paper was then wetted with the liquor, and hung to dry. When dry, each sheet was rolled up tight, and the outward edge pasted down, to prevent its opening; half a sheet, thus prepared, will burn 3 hours.

Quick Match.

The worsted or cotton must be laid evenly in an earthen or other pan, and the different ingredients poured over it, and about half the powder: being left a short time to soak, it is afterwards wound smoothly on a reel, and laid to dry, remaining half of the powder is then sifted over it; and it is ready for use when dry.

Note. The French have lately made their slow match by soaking the rope in a solution of sugar of lead and rain water: in the proportion of ¾ of an ounce of sugar of lead to one pint of water; and this, they esteem as preferable to the old sort.

MARCHING.—The Quick step, 108 paces per minute, each of 30 inches; making 270 feet per minute.