double-lead thread
51Drill bit — For the fictional character, see Drill Bit (Transformers). For the cancelled skyscraper nicknamed Drill bit, see Chicago Spire. For the types used in drilling wells, see Well drilling. From top to bottom: Spade, lip and spur (brad point), masonry …
52Japanese books — The book in Japan has had a long history, beginning in the late eighth century A.D. The majority of books were hand copied until the Edo period (1603 1867), when woodblock printing became comparatively affordable and widespread. Movable type… …
53Mathematics and Physical Sciences — ▪ 2003 Introduction Mathematics Mathematics in 2002 was marked by two discoveries in number theory. The first may have practical implications; the second satisfied a 150 year old curiosity. Computer scientist Manindra Agrawal of the… …
54Mary J. Blige — Blige performing live, September 2010. Background information Birth name Mary Jane Blige Born Ja …
55Josh White — Infobox musical artist Background = solo singer Instrument = Guitar Name = Josh White Img capt = Josh White in 1945 Born = February 11 1914 in Greenville, South Carolina (some sources incorrectly list his birthplace as Greensboro, NC) Died =… …
56industrial glass — Introduction solid material that is normally lustrous and transparent in appearance and that shows great durability under exposure to the natural elements. These three properties lustre, transparency, and durability make glass a favoured… …
57Ancient Chinese coinage — Ancient Chinese coins Chinese coins were produced continuously for around 2,500 years by casting in moulds, rather than being struck with dies as with most western coins. Contents 1 …
58Keith Moon — in 1975 Background information Birth name Keith John Moon Born …
59Chinese coins — Ancient Chinese coins were produced continuously for around 2,500 years by casting in moulds, rather than being struck with dies as with most western coins.Collectors can obtain affordable yet old, beautiful, and interesting coins associated with …
60Helix angle — In mechanical engineering, a helix angle is the angle between any helix and an axial line on its right, circular cylinder or cone. [ANSI/AGMA. ANSI/AGMA Standards 1012 G05 Gear Nomenclature, Definitions of Terms with Symbols. American Gear… …
