First-Fire Composition For The White Light

There are two different compositions used. One of them consists of -

Per cent.

Saltpete.....................

57.2

Sulphur (flour)....................

19

Antimony.................

19

Dextrin..................

4.8

The saltpeter and sulphur are first well mixed by hand and rubbed through a 15-mesh sieve. Antimony is added and mixed. Dextrin is added, and, after being well mixed by hand, the mass is screened through a 12-mesh sieve and then again thoroughly mixed. The case, loaded with the color composition to within 1/8 inch of the top, is then filled to the brim with the first-fire composition described above, and capped. This latter operation consists of forcing a cardboard disk into the open end of the case with the loaded composition and the first-fire composition and lightly tapping it into place.

Position Light - Red

The difference between the white and red lights is that the latter has a composition consisting of -

Per cent.

Chlorate of potash....................

37.5

Nitrate of strontium .....................

50.

Powdered orange shellac................

12.5

Compressing composition.

Fig. 182. - Compressing composition.

This composition is made up in the manner heretofore described, and is screened in order to get a homogeneous mass.

Position Light - Green

The green differs from the white position light only in the composition, which consists of -

Per cent.

Barium chlorate...............

23.3

Barium nitrate.................

59.2

Powdered orange shellac................

10.5

Potassium chlorate................

6.4

Stearin.................

.6

A batch consisting of 47 1/2 pounds is mixed in a manner similar to that described under the white-light composition.

Drumhead

In assembling either the white, red, or green light the same drumhead is employed. The red and green lights have no quick fire as the composition is easily ignitable. A muslin drumhead is put over the top of the case and pasted down on the sides in the manner previously described.

Case with drumhead.

Fig. 183. - Case with drumhead.

Prime on drumhead.

Fig. 184. - Prime on drumhead.

Prime Blob

This consists of -

Per cent.

Black antimony.....................

23.

Potassium chlorate................

46.3

Strontium carbonate.....................

30.7

The three constituents are thoroughly mixed and screened in the customary manner and the powder wet down to a paste by the use of gum water made by mixing 2 ounces of gum arabic dissolved in a pint of water. A puddle of this prime about 1/2 inch in diameter is formed on the muslin drumhead in the center, where a hole has been punched through.

Protecting Disk

The protecting disk is made from 50-pound strawboard cut 1 1/2 inches in diameter, with a hole in the center 3/4 inch in diameter.

Protecting and striker disks.

Fig.185. - Protecting and striker disks.

Figure 185 shows this disk at the right of the case.

Striker Disk

The striker disk is cut from a piece of 50-pound straw-board 1 1/2 inches in diameter. This disk is given a coating of composition consisting of -

Per cent.

Powdered glass.........................

80

Red phosphorous....................

20

This is thoroughly mixed and made into a paste by adding gum water. The striker is related to the blob in the same manner as the surface on our safety match box is to the head -of the match.

Cotton Batting

A small wad of cotton batting is formed into the hole in the protecting disk and acts as a protection to the prime blob.

Opening Tape

Cotton tape 1/2-inch wide and 5 inches long is placed between the protecting disk and the striker disk. Two staples hold the two disks firmly together with the tape between. The cotton in the protecting disk prevents an abrasion on the blob. Figure 185 shows the assembly. The tape protrudes beyond the lower edge of the band as shown in figure 186.

Staples

The staples are small wire staples of 7/16-inch No. 14 semi-spring wire used in assembling the striker and protecting disk. A stapling machine is employed to clinch them.

Identification Disk

This disk is placed upon the top of the light and is made of 50-pound strawboard cut to a diameter of 1 1/2 inches. Three different types of embossing characterize the three different lights, namely, the red, white, and green. Corrugations signify red; a concave surface signifies white and a convex surface signifies green. This identification disk is held in place by a binding band..

Binding band in place.

Fig. 186. - Binding band in place.