Abstract: An apparatus for maintaining a constant temperature within a vessel immersed in a liquid by surrounding a portion of the vessel, extending above the surface of the liquid, with a wick. The wick conducts liquid up to a predetermined point on the vessel and maintains the liquid at that point, regardless of changes in the level of the liquid due to evaporation. The wick is encased within a layer of heat insulating or heat conducting material to further aid in maintaining a constant temperature within the vessel. A second embodiment, including alternating layers of heat conducting and heat insulating material, is disclosed for increased temperature control. The disclosed apparatus is particularly useful for maintaining a constant temperature within a vessel attached to a scientific instrument, such as a pore volume and surface area analyzer.

Abstract: A continuous volume measuring device for measuring the cumulative volume of a flowing fluid. The device includes a pair of coupled expandable chambers, and the fluid flow is directed into a first chamber to expand it while the second chamber is contracting and expelling liquid therefrom, the expansion of the first chamber being measured to determine the volume of fluid being received therein. When a predetermined volume of liquid is received, a valve means diverts the fluid flow to fill the second chamber, the expansion of which is similarly measured, and the first chamber is emptied. In the preferred embodiment, the chambers are precision syringes.

Abstract: An apparatus for maintaining a constant temperature within a vessel immersed in a liquid by surrounding a portion of the vessel, extending above the surface of the liquid, with a wick. The wick conducts liquid up to a predetermined point on the vessel and maintains the liquid at that point, regardless of changes in the level of the liquid due to evaporation. The wick is encased within a layer of heat insulating or heat conducting material to further aid in maintaining a constant temperature within the vessel. A second embodiment, including alternating layers of heat conducting and heat insulating material, is disclosed for increased temperature control. The disclosed apparatus is particularly useful for maintaining a constant temperature within a vessel attached to a scientific instrument, such as a port volume and surface area analyzer.