To find the number of vibrations, the length of pendulum being

given.

Rule.-Multiply 60 seconds by the square root of 39.14, divided by the length of the given pendulum.

Or say, As the given length is to the standard length, so is the square of 60 (its vibrations per minute) to the square of the number required.

ROCKETS, WAR.

Two kinds-1st. Boxer's improved Congreve. 2nd. Hale's. Of both there are 3, 6, 12, 24 pounders. Hale's rocket has no stick, being kept point foremost by the aerotation given from the gas pressing against 3 curved shields fixed to the three vents.

ROCKETS, LIFE SAVING, BOXER 12 POUNDER.

These are fixed to carry a line over a stranded vessel, and establish a communication by means of which a hawser carrying a sling, and also a line for running the sling along the hawser are made fast to the highest possible point available on the masts. Two or three men may travel together on the sling. No rule can be given as to speed, which must depend on the distance of the vessel. It is very important to avoid fouling.

MACHINE, ROCKET.

For Congreve rockets there are three kinds-1. Siege. 2. Field. 3. Sea-service. Some modifications will be adopted for Hale's rockets.

PART IV.

ARTILLERY EXERCISES.

PART I.*-Telling off the Detachments.

1. In the service and exercise of the various descriptions of ordnance, the same numbers, as far as possible, always perform the same duties; the detachments being told off upon the same principle, viz., beginning with the lowest numbers, and proceeding to the highest; No. 1 always commanding.

2. It is presumed that not less than six men will be posted to any description of ordnance. When the detachment consists of less than six men, the higher numbers are struck out and additional duties are imposed on those remaining.

3. The detachment falls in, two deep, in close order, No. 1 tells them off from the right; 2 being the right hand man of the rear rank; 3 the right hand man of the front rank; 4 the second man from the right of the rear; 5 the man in his front, and so on. The detachment is also told off into two sections.

NAMES OF THE PRINCIPAL PARTS OF A FIELD GUN CARRIAGE.

• Extracted from "MANUAL OF ARTILLERY EXERCISES;" the Parts and Sections being similarly numbered. Many of the details are necessarily omitted, being too long for the limited size of "THE ARTILLERIST'S MANUAL, ETC.”

Commander's words are printed in SMALL CAPITALS,
Executive ditto

Italics.

S. 2. Posts of the Detachment.

1. In Action, and before the Word Load.-No. 1 at the point of the handspike. 2 and 3 outside the wheels; with howitzers rather in rear of the muzzle; with guns in line with the front of the wheel. 4 and 5 in line with the breech. 6 five yards in rear of the left wheel. 7 in rear of the limber. 8 on left of 7. 9 four yards in rear of the limber. The whole facing the gun.

When in action the front is towards the muzzle; when limbered up the front is towards the horses.

2. In Order of March.-No. 1 on the off side of the wheel horses' heads. 2 and 3 in line with the muzzle; 4 and 5 in line with the breech; 6 and 7 in line with the axletree of the limber; 8 and 9 in line with the splinter bar. The whole at the distance of one yard from the wheels.

3. In Front. In line ten yards in front of the leading horses; 1 on the right of the detachment.

4. In Rear. In line two yards in rear of the muzzle of the gun; 1 on the right of the detachment.

5. Right, or Left.-In line with the gun axletree, one yard to the right, or left of the wheel.

6. Mounted.-Nos. 1 and 6 on the gun limber ; 1 on the right, 6 on the left. 5 and 4 on the waggon limber; 5 on the right, 4 on the left. 3 and 2 on the front of the waggon body; 3 on the right, 2 on the left. 7 and 8 on the rear of the waggon body; 7 on the right, 8 on the left. 9 between 5 and 4.

S. 3. Change of Position of Detachments.

To form the Order of March from Detachment Front.-" FORM THE ORDER OF MARCH. Right Face, double march. 2 and 3 open out. Each number halts when at his post; and they front by signal from 2, who faces about immediately he arrives at his station.

2. From Detachment Rear, or Left, or Right." FORM THE ORDER OF MARCH." Left face, double march. When the detachments are in the rear, or on the right they proceed direct; but when on the left they countermarch. Each number halts when at his post.

3. Change from Front to Rear." DETACHMENTS REAR.' Right face, double march. When the detachment clears the gun. Rear turn, right turn, halt, front.

4. From Rear to Front.-" DETACHMENTS FRONT." double march, front turn, left turn, halt, front.

5. From Rear to Right or Left.-" DETACHMENTS left). Right or left face. Double march, front turn. with the axletree, Halt,

Right face,

RIGHT," (or When in line

6.-From the Order of March to form Detachments to the Rear.— "DETACHMENTS REAR." Right about face. Double March. 2 and 3 close to the centre, and wheel to their left. Nos. 1 give Halt, front.

7. To the Front.-" DETACHMENTS FRONT." Double March.