Abstract: Percussion device for triggering the primer of a blasting charge of an actuation device. It comprises a striker (4) moveably housed and retained in a support (1), as well as a helical traction spring (7) of which one end (8) is secured to the striker. The other end (9) of the spring (7) is provided with a hook member (10) allowing to maintain the spring in a tensioned state and to suddenly release the spring to cause the percussion by spring contraction. The invention is particularly applicable to devices to sever cables, for example on boats, in case of dismasting.

Abstract: The present device comprises a tubular sleeve (1) which is opaque and which surrounds a part of the length of a tube (2), and provided with an observation window (3) permitting the appearance of the level (4) of a liquid contained in a first tubular compartment (5) forming part of a system of communicating vessels. An annular chamber (10) communicates with the compartment (5), particularly by way of a second compartment (12) and a connecting conduit (11). The ratio between the section of the annular chamber (10) and that of the tubular compartment (5) is such that the variation in the liquid level is very strong in this compartment as compared with that in the annular chamber.The invention is particularly applicable to a sighting device for a mortar.

Abstract: The invention relates to a disposable syringe which is not able to be used more than once for carrying out an injection.To this end, the syringe comprises means which permit the rearward return of at least a part of the piston body to be prevented when the said body occupies a position close to its position of maximum insertion in the cylinder. These means can, for example, be formed by a circular groove, in which can be engaged a peripheral rim of a resilient member integral with the body of the piston, thus causing the blocking of the said body.Applications are particularly in human and veterinary medicines.

Abstract: A grapnel is disclosed which comprises a plurality of arms pivotably mounted on a substantially rod shaped body. The arms have at their free ends catching points forming an angle with the arms and near the foot of the catching points auxiliary catching claws extend substantially in the direction of the arms. A piston and cam-shaped portions of the grapnel arms co-operate to urge the arms into an outwardly extending position upon a traction on the grapnel rope.