Abstract: A qualitative indication of the pressure in a pneumatic tire is provided by a sliding marker in a sleeve. The marker moves in a chamber formed by a hollow lens closing one end of the sleeve and a diaphragm within the sleeve. A spring forces the marker toward the diaphragm and air pressure from the tire is applied to the opposite side of the diaphragm from the marker. A pressure above a predetermined amount is indicated by the end of the marker substantially filling the hollow lens and a pressure below the predetermined amount is indicated by the end of the marker withdrawing into the sleeve.

Abstract: A toy top having an air impeller-driven flywheel and a spring-latch mechanism which releases an upper portion of the top from a lower housing when an articulated arm of the spinning top comes into contact with an object such as a stationary object or another top. The flywheel located inside the lower housing is rotated by blowing air into one of two ducts on the housing. The stream of air comes into contact with the blades of an impeller causing rotation of the impeller and the flywheel which is attached to the impeller. The flywheel is attached to a shaft rotatably mounted inside the housing. Slots in bosses extending upward from the housing releasably engage a plate at the bottom of the upper portion. The slots disengage from the plate when one of two articulated arms of the spinning top contacts an object allowing a spring mounted inside the upper portion to push the upper portion away from the lower housing. The top appears to "blow up" as the upper portion pops up from the housing.