No. 1. - In this formula, saltpeter, sulphur, and charcoal are the constituents. The general consensus of opinion of the manufacturers is to the effect that this formula, which is the driving charge of rockets, will not deteriorate on protracted storage; however, it has been pointed out by one of the manufacturers that changes in temperature might cause a separation of the compressed charge from the wall of the tube, due to the fact that there is a different coefficient of expansion between the compressed mass and the tube, which would cause the driving charge to operate too sharply and not to function as originally designed.

No. 2. - This formula consists of saltpeter, sulphur, and arsenic disulphide, and is used in the rocket-smoke compositions. The consensus of opinion of manufacturers seems to indicate that the combination of saltpeter, sulphur, and arsenic disulphide. is a stable mixture and will not deteriorate.

No. 3. - In this formula, barium nitrate, aluminum powder, aluminum flake, or bronze, and sulphur are used for the rocket white-signal composition. The consensus of opinion seems to point to the stability of this mixture.

No. 4 - In this formula, strontiumi nitrate, potassium chlorate, and orange shellac, finely powdered, are used for rocket red signals. One of the manufacturers states as follows:

"This is a dangerous composition, and mixtures of this kind should be kept from all other explosive materials, for the reason that they have a tendency to sympathetic explosion. Such mixtures are extremely active, and with a small percentage of moisture,, are, in addition, very danger-oils from the standpoint of safety."

It is further pointed out that strontium nitrate tends to absorb moisture from the air. This absorbed moisture will dissolve some potassium chlorate, which solution passes through the walls of the containing tube by capillary action, subsequently forming fine needlelike crystals on the outside. These crystals prevent the proper functioning of the piece and add an element of great danger.

No. 5. - In this formula, barium chlorate, barium nitrate, and orange shellac, powdered, are used. This composition, as reported by one of the manufacturers, is both dangerous and treacherous, on account of the presence of barium chlorate, since chemical reaction may take place. It is not clear, nor are there any records available, as to what chemical reaction actually takes place; the inference being, however, that an acid develops on standing, which in combination with the chlorate and the fine organic powder, such as shellac, makes this mixture rather treacherous.

No. 6. - In this formula, barium nitrate, aluminum powder, and aluminum flake, or bronze, are used. This, according to the manufacturers, appears to be a safe mixture.

No. 7. - In this formula, potassium chlorate, strontium carbonate, and orange shellac are used. We have not obtained any definite recommendations in regard to this mixture, but, due to the fact that the composition contains approximately 15 per cent. of strontium carbonate, the chances of the development of a free acid seem to be more or less remote, and we would be inclined to regard this mixture as other than in the treacherous or dangerous class.

No. 8. - This composition consists of barium chlorate and shellac. Criticisms might be made regarding this mixture that have been previously made where chlorates and finely powdered organic materials are mixed. There appear to be no data in regard to the stability of this mixture and, in the absence of further information, we would be inclined to include it with formula No. 5, although the presence of barium nitrate in the latter formula would probably make it more dangerous than the simple mixture of barium chlorate and orange shellac.

No. 9. - This formula consists of barium nitrate, sulphur, aluminum powder, antimony sulphide, and stearin. The dangerous constituent in this mixture is the antimony sulphide, which, according to the manufacturers, has a tendency to develop acid. However, it is pointed out that if the antimony sulphide is kept down to a reasonably low per cent. this danger is minimized.

No. 10. - This consists of potassium chlorate, strontium nitrate, and orange shallac, powdered. As this composition has the same ingredients as No. 4, except that the proportions are different, we would give it the same classification as No. 4.

No. 11. - This consists of barium chlorate, barium nitrate, potassium chlorate, shellac, and stearin. It is classified by manufacturers as unsafe, the same argument being used as in the case of No. 5 composition.

No. 12. - This consists of saltpeter, arsenic disulphide, sulphide of antimony, sulphur, and dextrin. Beferring back to the discussion under formula No. 9, we have pointed out criticisms made by manufacturers in reference to the amount of antimony sulphide in the compositions where the percentage is rather large. We would, therefore, classify this mixture as dangerous.'

No. 13. - Here barium nitrate, flaked aluminum, powdered aluminum, sulphur, and castor oil are used. This composition is rated by the manufacturers as one of the safest.

No. 14. - Here barium nitrate, potassium nitrate, shellac, powdered, and sulphur are used. This composition is regarded as safe by the manufacturers.

No. 16. - Here strontium nitrate, sulphur, aluminum powder, and orange shellac are used. This is likewise regarded as reasonably safe.

No. 16. - Here potassium nitrate, pitch, powdered borax, chalk, sand, and sulphur are used. This also is regarded as reasonably safe.

No. 17. - In this formula saltpeter, sulphur, antimony sulphide, and meal powder are used. The same argument as previously made in reference to the presence of antimony sulphide applies in this case, and the manufacturers regard the mixture as dangerous.

No. 18. - This consists of potassium chlorate, red gum, and charcoal. It is regarded as a dangerous mixture.

No. 19. - This is composed of red phosphorus, fine charcoal, and gum arabic. The presence of red phosphorus is indicative of the treacherous character of this composition, and it should be regarded as dangerous.

No. 20. - This is composed of meal powder and ground shellac, and is regarded as safe.

Nos. 21, 22,23. - These are not specified by formulas. Any formula for detonating caps and matches would be indicative of an unsafe composition. The rifle smokeless powder mentioned in No. 23 may be stored with reasonable safety.