Abstract: An apparatus for mixing multi-part reaction materials under a vacuum comprises a container including a mixing chamber sized to contain a reaction material. An agitator for mixing the reaction material to form a mix includes both rigid blades and flexible paddles. The rigid blades are substantially non-deflected during mixing and cut the mix, and the flexible paddles are deflected and knead the mix. The combined action of the rigid blades and the flexible paddles under vacuum throughly mixes reaction materials and removes entrapped gases from the mix. The mix can be dispensed directly from the mixing chamber. The apparatus can be used to mix viscous materials such as bone cement.

Abstract: A slide arrester mounted on a ski pole near the handle grip, comprising an arcuately-shaped blade pivotable between stowed and projected positions. A spring arm yieldably holds the blade in either position with an overcenter snap action, while a cutting tip formed on the free end of the blade is sheathed in a recess in the handle grip in the stowed position.

Abstract: Means for exhausting the fumes arising from material being mixed in a mixing bowl, the fumes being drawn off and passed through a filter that removes the noxious materials and returns the air to the room in which the bowl is located. The device is particularly adapted for use in surgical operating rooms where the utmost precautions must be taken to prevent the inhalation of any fumes by the patient and where sterility must be maintained at all times during the operation.