Abstract: A collapsible hair or massage brush has a body divided into two flat, superposed members in the form of slotted plates or frames which are limitedly relatively shiftable in a predetermined direction to swing a multiplicity of bristle carriers, normally retracted into the body, through substantially 90.degree. into a working position in which their bristles project perpendicularly from one of the body surfaces. The bristle carriers are journaled in one of the members by pivotal axles transverse to the shift direction, these axles being either individual to the respective carriers or common to groups of them lying in parallel rows. The carriers or their axles have coupling formations engaging coacting camming formations on the other member.

Abstract: A photosensitive surface is enclosed behind a wall formed with a vertically open slit which forms with the surface a vertical angle of 80.degree.. This slit is open about 3.degree. and is displaced horizontally past the surface through at least 150.degree. so as to let parallel rays of sunlight fall onto this surface and suppress diffuse nonparallel ground light. The wall can be carried on a support also carrying the photosensitive surface, e.g. a photoresistor, photocell, or photodiode, which is used to control an awning, roller blinds, or the like.