adjust a diaphragm
31Photography — is the art, science and practice of creating durable images by recording light or other electromagnetic radiation, either electronically by means of an image sensor or chemically by means of a light sensitive material such as photographic… …
32Pan flute — Pipes of Pan redirects here. For other uses, see Pipes of Pan (disambiguation). Andean panflute, or zampoña. The pan flute or pan pipe (also known as panflute or panpipes) is an ancient musical instrument based on the principle of the closed tube …
33Sound reinforcement system — A sound reinforcement system is an arrangement of microphones, electronic signal processors, amplifiers, and loudspeakers that makes live or pre recorded sounds usually music or speech louder, or that distributes the sound to a larger or more… …
34Nikkormat — Nikomat Nikomat FT Type 35mm SLR camera Lens mount Nikon F mount Focus manual Exposure Man …
35Cat's-whisker detector — Galena cat s whisker detector Precision cat s whisker d …
36birth control — regulation of the number of children born through the deliberate control or prevention of conception. Cf. family planning (def. 1). [1914, Amer.] * * * Voluntary limiting of human reproduction, using such means as contraception, sexual abstinence …
37Alexander Graham Bell — Infobox Person name = Alexander Graham Bell image size = 225px caption = Portrait of Alexander Graham Bell c. 1910 birth date = 3 March 1847 birth place = Edinburgh, Scotland, UK death date = death date and age|1922|8|2|1847|3|3|df=y death place …
38Microelectromechanical systems — (MEMS) (also written as micro electro mechanical, MicroElectroMechanical or microelectronic and microelectromechanical systems) is the technology of very small mechanical devices driven by electricity; it merges at the nano scale into… …
39Snake — Ophidian redirects here. For the professional wrestler, see The Osirian Portal. This article is about the animal. For other uses, see Snake (disambiguation). Snakes Temporal range: Early Cretaceous – Recent, 112–0 Ma …
40Compass — This article is about the direction finding instrument used in navigation. For other uses, see Compass (disambiguation). A simple dry magnetic pocket compass …
