Abstract: A laser device includes a laser configured to generate laser light and a laser control module configured to receive at least a portion of the laser light generated by the laser, to generate a control signal and to feed the control signal back to the laser for stabilizing the frequency, wherein the laser control module includes a tunable frequency discriminating element which is preferably continuously frequency tunable, and where the laser control module is placed outside the laser cavity.

Abstract: A fluid container, especially one formed of plastic, including a hollow body and a neck portion with an opening at the end thereof. A breakable seal for holding the fluid in the container is positioned in the neck between the hollow body and the container opening at the end of the neck. A cap at the container opening is optional but preferred. With the cap removed and the container tilted up side down with the container opening positioned inside or above the fluid receptacle, compression of the outside of the neck adjacent or nearly adjacent to the seal inside the neck, as applied with thumb and forefinger, causes the seal to break or separate allowing fluid to flow from the container into the receptacle without spillage.

Abstract: The several embodiments include a hypodermic needle with a hollow member positioned over a portion of the needle, thus covering that portion of the needle. Prior to and during use, the hollow member is held away from the piercing end of the needle to allow it to be used in the normal manner. After the needle has become contaminated, a simple action by the user places the hollow member in a position covering the piercing end of the needle, and the hollow member is supported in this position against rearward pressure. The hollow member is similarly kept from sliding off the end of the needle.

Abstract: In the several embodiments, the tire chain, and a method of installing a tire chain in which a line extends from each of the opposite ends of the portion of the tire chain that encircles the inside of a tire. In a preferred embodiment, the two lines cross the treaded portion of the tire diagonally, so that one line crosses the other, and are connected to the portion of the tire chains that encircle the outside of the tire. Preferably, the two lines are connected to each other at the point where they cross, which is about at the center of the treaded surface of the tire.

Abstract: A fire fighting device consisting of a jet engine, or alternatively another wind-producing mechanism, with a conduit mounted thereon, the conduit having an opening so that when water or another fire retardant is directed into the conduit, the water or other fire retardant will exit the opening and enter the jet exhaust when the jet engine is in operation. The jet exhaust will carry the water or other fire retardant for a long distance, thus enabling fire fighters to propel the water or other fire retardant to distant parts of a wildfire by aiming the jet exhaust above the fire. Preferably, the jet engine is mounted in a manner allowing rotation on horizontal and vertical axes to allow it to be aimed.