There are various types of position lights, often called Bengal lights.

The position light is commonly used to indicate the location of trenches to aerial observers. But it is available also for other purposes. The light is made to burn with a white illumination, a red illumination, or a green illumination. These pyrotechnic articles are relatively small; can be transported with ease and are extremely efficient for illuminating purposes as well as for signaling.

Position light.

Fig. 174. - Position light.

The position light is small, cylindrical in form, 2 1/2 inches high by 1 1/2 inches inside diameter, loaded with an illuminating composition and resembling closely the rifle light. The method of firing it is very similar to that used for the smoke torch.

Sectional drawing of position light.

Fig. 175. - Sectional drawing of position light.

Position Light

1. Case.

2. Case-bottom disk.

3. Composition.

4. First-fire composition.

5. Drumhead.

6. Prime blob.

7. Protecting disk.

8. Striker disk.

9. Cotton batting.

10. Opening tape.

11. Staples (not shown).

12. Identification disk.

13. Binding band.

14. Waterproofing.

15. Label.

16. Tearing cord.

17. Inside wrapper.

18. Outside wrapper.

19. Drumhead.

20. Identification tag.

21. Outside label.

22. Packing.

Case

The case is a small paper cylinder rolled by hand on a mandrel in the method previously described. The paper used being Bogus 0.013. The case should have an inside diameter of 1 1/2 inches and a height of 2 1/2 inches. Bogus paper is used, because this paper burns readily and will not produce a chimneying effect.

Case-Bottom Disk

The case-bottom disk is stamped out of 50-pound straw-board and has a diameter of 1 1/2 inches. In assembling the disk in the bottom of the case, the inside of the case is first wiped with glue close to the bottom, and while the glue is still wet, the bottom disk is dropped in at the other end and forced into place flush with the bottom. The article is allowed to dry before the composition is added.

Composition For White Light

This composition is -

Per cent.

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

66.9

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

16.7

Flake aluminum....................

15.5

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

.6

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

.3

Twenty-eight pounds of barium nitrate and 7 pounds of sulphur are mixed by hand and rubbed through a 16-mesh sieve. After screening they are again well mixed by hand; 6 1/2 pounds of flake aluminum and 1/4 pound of black • antimony are now added to the mixture, which is again sifted through a 16-mesh sieve, and 1/8 pound of stearin is added. The whole mass is thoroughly mixed by hand, and screened through a 12-mesh sieve. It is then given a final thorough mixing by hand. It is to be noted here that no powdered orange shellac is added to the mixture as in the case of the rifle light, the stearin acting as the binder. This mixture may be loaded in the case by hand, in a manner similar to that previously described, by using a mallet and wooden plunger, which drive the charge home to within 1/8 inch from the top of the case. Or a machine may be used for loading.

Machine For Loading

This is a simple hand-lever-operated machine or press used for charging position-light cartons. It consists of a movable platform on which are placed cases to be loaded, and a stationary head which carries the plungers or rammers. The principle of this machine is analogous to that used in charging the rocket bodies, except that hand power is substituted for hydraulic.

Before being placed under the plungers for pressing, the light cases are assembled on a jig, consisting of a wooden base block with a rack or frame having 10 brass cylinders.

The assembled cases are shown in figure 177.

This operation is accomplished by removing the rack of cylinders from the base block, inverting it and placing the paper cartons in the cylinders, and then setting the base block on the support of the rack and turning the whole to its normal position as shown in figure 177.

The brass cylinders are 2 1/4 inches long, and have for 3/8 of an inch an internal diameter of 1 5/8 inches, that being the outside diameter of the case to be charged. The balance of the length of the cylinder has the same diameter as the inside of the case, which is 1 1/2 inches.

Figure 177 shows the measuring tray, which consists of a sliding frame approximately 3 1/2 inches in thickness, through which are bored 10 holes, as shown in the picture. This 1 3/4-inch board may be moved by hand forward and backward across the face of a supporting board or plank, which is 13/4 inches in thickness and acts as a shutter, closing and opening the several orifices. The holes in the upper plank, when in position as shown in the photograph, register with the holes in the lower plank, thus permitting a measured charge to be introduced into the carton.

Figure 178 shows the operation of filling the loading frame with composition by hand.

Charging measuring frame.

Fig. 178. - Charging measuring frame.

Figures 178,179,180, and 181 show the hand operation of filling the cavities in the board to their brim with composition.

Figure 179 shows the operator removing the excess composition.

Loading rack and measuring tray.

Fig. 177. - Loading rack and measuring tray.

Removing excess from measuring frame.

Fig. 179. - Removing excess from measuring frame.

Measuring frame in unloading position.

Fig. 180. - Measuring frame in unloading position.

Measuring frame unloaded.

Fig. 181. - Measuring frame unloaded.

Figure 180 shows the measuring frame in position to discharge its several charges into the cartons.

Figure 181 shows the top block after the charges have been discharged, the operator having manipulated the sliding frames into a position where the orifices in each register, so that the contents are allowed to fall through and into the carton. One charge of composition is measured into the cartons in this manner, then the loading block is placed in the pressing machine.

Figure 176 shows the introduction of the cartons under the plungers of the hand press. The loading block is taken from the press, and a second charge is measured and pressed into the cases, in the same manner as before.

Light cases assembled on loading machine.

Fig. 176. - Light cases assembled on loading machine.

Figure 182 shows the position of the plungers after the operator has driven them home, thus pressing the charge into the cartons. The pressure exerted by the operator is magnified by means of the two cams beneath the loading block of the machine, as shown in the photograph. When the charges are rammed home in the cartons they fill the cartons to within 1/4 of an inch of the top. In removing the cartons from the press, the base block, holding the loaded cartons and their brass guides, is removed from the machine and the guides are lifted off from the cartons. The topping charge is then added to the case in the same manner as in the hand-loading operation.