Abstract: A gauge for assessing the content of releasable gas in a bottle of compressed or liquified gas, which gauge serves to determine the force required to cause the bottle to pivot about a point on its lower periphery, the weight of the content being assessed from the magnitude of said force. The gauge has a platform pivoted about a horizontal edge on a frame and is spring-urged upwardly so as to be suitable for positioning under the lower rim of a gas bottle at a point on the periphery thereof. This causes the bottle to pivot about a diametrically-opposed point on the bottle rim periphery, provided the spring exerts a sufficient force. The platform is connected to a pointer to cause the pointer to sweep across a scale provided on a part of the frame, dependent upon the movement of the platform.