hill-spacing
41Optacon — The Optacon (OPtical to TActile CONverter)[1] is an electromechanical device that enables blind people to read printed material that has not been transcribed into Braille. Contents 1 Description 2 History …
42San Carlo alle Quattro Fontane — Church of Saint Charles at the Four Fountains San Carlo alle Quattro Fontane (Italian) Facade of Church of San Carlo alle Quattro Fontane by Francesco Borromini Basic information …
43Colloidal crystal — A colloidal crystal is an ordered array of colloid particles, analogous to a standard crystal whose repeating subunits are atoms or molecules.[1] A natural example of this phenomenon can be found in the gem opal, where spheres of silica assume a… …
44Recall (memory) — Recollection redirects here. For other uses, see Recollection (disambiguation). Recall in memory refers to the retrieval of events or information from the past. Along with encoding and storage, it is one of the three core processes of memory.… …
45Moa — This article is about the extinct New Zealand birds known as moa. For other uses, see Moa (disambiguation). Moa Temporal range: Miocene Holocene, 17–0 Ma …
46Pencil-tailed tree mouse — Pencil tailed tree mice Temporal range: Late Pliocene to Recent Scientific classification Kingdom: Animalia Phylum: Chordata Class …
47Double-slit experiment — Slit experiment redirects here. For other uses, see Diffraction. Quantum mechanics …
48Kilogram — Kg redirects here. For other uses, see Kg (disambiguation). Kilogram A computer generated image of the international prototype kilogram (IPK). The IPK is the kilogram. The IPK, which is roughly the size of a golf ball, sits here alongside a ruler …
49Personal rapid transit — ation concept that offers on demand, non stop transportation, using small, independent vehicles on a network of specially built guideways. Several different designs have been proposed, and as of 2008, at least one is under… …
50AC power plugs and sockets — See also: Industrial and multiphase power plugs and sockets Plugs and sockets may sometimes combine male and female contacts, but t …
