Abstract: A mask for providing and protecting the shear edge of a mold from contact with oversprayed powder directed onto the wall of the mold cavity. The mask comprises an air flow duct having an opening located adjacent the shear edge of the mold. First and second air flow control members are adjustably mounted upon the duct adjacent the air flow opening. The first and second air flow control members have opposed edges spaced apart so as to define an air flow gap therebetween, which air flow gap is operable to direct an airstream from said duct onto the shear edge of the mold so as to effectively mask that shear edge from powder sprayed onto the cavity defining portion of the wall of the mold.

Abstract: An integrated tubal by-pass fishway system for use at dams, obstructions and the like, which enable fish to swim freely and safely upstream or downstream on a near natural level with the original stream bed, by-passing the dam or obstruction by means of a tubal fishway system without the aid of ladders, locks, nets, lifts, etc. Included in this system are several devices that attempt to mimic some of the natural aspects of the original stream without upsetting the present environment, without interferring with present activities on the stream and without requiring constant maintenance. The system is devoid of mechanical devices, although certain devices may be added to monitor fish migration, procure fish samples, etc. Since experience with certain anadromous species of fish indicates that fish ladders, locks, etc.