annular cutting
11fern — fernless, adj. fernlike, adj. /ferrn/, n. any seedless, nonflowering vascular plant of the class Filicinae, of tropical to temperate regions, characterized by true roots produced from a rhizome, triangular fronds that uncoil upward and have a… …
12Fern — /ferrn/, n. a female given name. * * * Any of about 10,000–12,000 species (division Filicophyta) of nonflowering vascular plants that have true roots, stems, and complex leaves and reproduce by spores. Though ferns were once classified with the… …
13differential geometry — Math. the branch of mathematics that deals with the application of the principles of differential and integral calculus to the study of curves and surfaces. * * * Field of mathematics in which methods of calculus are applied to the local geometry …
14Magnitude of eclipse — Not to be confused with apparent magnitude, the logarithmic scale of astronomical brightness. An annular solar eclipse has a magnitude of less than 1.0 The magnitude of eclipse or geometric magnitude is the fraction of the diameter of the… …
15Drill 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 …
16Knurling — Close up shot of a diamond pattern knurling on a cylindrical work piece. Knurling method: left/right with tips raised, spiral angle: 30°, pitch: 1 mm, profile angle: 90° Knurling is a manufacturing process, typically conducted on a lathe, whereby …
17Lathe — A lathe (pronEng|ˈleɪð) is a machine tool which spins a block of material to perform various operations such as cutting, sanding, knurling, drilling, or deformation with tools that are applied to the workpiece to create an object which has… …
18tunnels and underground excavations — ▪ engineering Introduction Great tunnels of the world Great tunnels of the worldhorizontal underground passageway produced by excavation or occasionally by nature s action in dissolving a soluble rock, such as limestone. A vertical opening …
19Rolls-Royce Olympus — Olympus Preserved Bristol Siddeley Olympus Mk 301 Engine Change Unit (ECU) complete with ancillaries and bulkheads. Type …
20Headward erosion — is a fluvial process of erosion that lengthens a stream, a valley or a gully at its head and also enlarges its drainage basin. The stream erodes away at the rock and soil at its headwaters in the opposite direction that it flows. Once a stream… …
