Abstract: A passive method for protecting flying birds against the danger of colliding into transparent barriers is disclosed. The method involves placing on the transparent barrier an image of the center portion of the web of an orb web building spider especially including in the image an adornment on the web known as the stabilimentum. The stabilimentum is known to be an advertisement by the spider for the purpose of deterring birds from flying into the web, an event which both animals wish to avoid. When the spider web image is placed on the transparent barrier, flying birds will take evasive action and thus avoid harmful collisions. Since the spider web image is mostly transparent, it does not block out a large portion of the transparent barrier.

Abstract: A solar heat collector having a collector element made from interconnected tubular members, each of which is provided with a transverse baffle, the baffles have openings forming spillways over which heat exchanging liquid passes. The collector element is preferably made from a plurality of tandem arranged sheet metal soft drink or beer cans, the ends of certain cans being removed before the cans are assembled. One or a plurality of collector elements are disposed along an incline such as a roof and a pump feeds liquid to the upper end or ends of the inclined collector element or elements to cascade down through each element and be heated by heat absorbed into the metal from the sun's rays. The heated liquid is then fed through a pipe or pipes from the lower end of each collector.