Abstract: A selfsustaining ladder, especially designed for use in harvesting fruit from trees, having an arcuate curvature to generally conform to the horizontal curvature of a segment of a fruit tree. The ladder has more than two uprights and the rungs, each of which connect with all of the upright, are spaced at considerable distances apart to provide maximum accessibility, between the rungs, to the fruit.

Abstract: A self cleaning air cleaner for a tractor engine which is capable of functioning either alone for cleaning air being supplied by suction to a carburetor of a gasoline engine or to the turbocharger of a diesel engine, or which can function as a pre-cleaner for air being supplied to a conventional air filter.

Abstract: An apparatus including a mixing tank connected to a source of water supply under pressure, by which the tank can be partially filled with water to be mixed with a poison in powder form, which is admitted to the tank through an access opening, normally closed by a transparent cover forming a window through which the mixing operation can be observed. Spray heads connected to the water supply source spray water across the top of the tank to settle dust from the poison powder, and a suction means communicating with the top part of the tank extracts poisonous fumes, caused by the powder, from the tank and discharges such fumes into a purifying unit from which purified air only is discharged. A pump connected to an outlet of the tank discharges the mixture under pressure to spray heads or other discharge means after first recirculating the mixture to complete the mixing operation.