Abstract: A scaffold structure for attachment to wall surfaces. Telescoping horizontal members are supported at an inner end by a secured wall bracket. The horizontal members are usable to carry a work platform resting on their upper surfaces. They are supported intermediate their ends by a depending bracket mounted to either a vertical post resting on a ground surface or an angular support extending upward from a lower wall bracket. Their outer ends include vertically open brackets for mounting vertical boards to serve as ground supports and/or handrail supports. A protective handrail can be mounted to the vertical boards at the outer ends of the horizontal members. An upright fixed adjacent to the outer end of each horizontal member is intersected by a roof member to provide an alternate form of outer support.

Abstract: A manual pipette adapted to use disposable plastic tips into which a liquid is drawn and from which it is dispensed is provided with means for dislodging the tip from the pipette after use. The disposable tip which is normally frictionally held at the distal end of the pipette is pushed off the pipette by a sleeve member that is slideably mounted on the barrel of the pipette.