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gh the center of the curve, perpendicular to the line through the two foci. -- Conjugate diameters (Conic Sections), two diameters of an ellipse or hyperbola such that each bisects all chords drawn parallel to the other. -- Conjugate focus (Opt.) See under Focus. -- Conjugate mirrors (Optics), two mirrors so placed…

e mixed into a paste with the addition of acetone and pressed out into cords (of various diameters) resembling brown twine, which are dried and cut to length. A variety containing less nitroglycerin than the original is known as cordite M. D.

in man, yellowish, biconcave, circular discs varying from 1/3500 to 1/3200 of an inch in diameter and about 1/12400 of an inch thick. They are composed of a colorless stroma filled in with semifluid hæmoglobin and other matters. In most mammals the red corpuscles are circular, but in the camels, birds, reptiles, and t…

An instrument to measure the height and diameter of trees.

Having the vertical diameter shorter than the horizontal or transverse; -- said of the bodies of animals, or of parts of the bodies.

Pertaining to a diameter; diametrical. Diametral curve, Diametral surface (Geom.), any line or surface which bisects a system of parallel chords drawn in a curve or surface. -- Diametral planes (Crystal.), planes in which two of the axes lie.

Of or pertaining to a diameter.

rential windlass, or Chinese windlass, a windlass whose barrel has two parts of different diameters. The hoisting rope winds upon one part as it unwinds from the other, and a pulley sustaining the weight to be lifted hangs in the bight of the rope. It is an ancient example of a differential motion.

One twelfth part of the diameter of the sun or moon; -- a term used to express the quantity of an eclipse; as, an eclipse of eight digits is one which hides two thirds of the diameter of the disk.

Neither shall ye diminish aught from it. Deut. iv. 2. Diminished column, one whose upper diameter is less than the lower. -- Diminished, or Diminishing, scale, a scale of gradation used in finding the different points for drawing the spiral curve of the volute. Gwilt. -- Diminishing rule (Arch.), a board cut with a…

doubleimage micrometer applied to the eye end of a telescope for measuring accurately the diameter of the image of the object glass there formed; which measurement, compared with the actual diameter of the glass, gives the magnifying power.

ion of a circle, or an oblique section of a cone through its opposite sides. The greatest diameter of the ellipse is the major axis, and the least diameter is the minor axis. See Conic section, under Conic, and cf. Focus.

reference to the figure of the earth, the difference between the equatorial and polar semidiameters, divided by the equatorial; thus, the ellipticity of the earth is

the wood in the form of bundles or threads, irregularly distributed throughout the whole diameter, not forming annual layers, and with no distinct pith. The leaves of the endogens have, usually, parallel veins, their flowers are mostly in three, or some multiple of three, parts, and their embryos have but a single cot…

all restraints. Barrow. Enlarging hammer, a hammer with a slightly rounded face of large diameter; -- used by gold beaters. Knight. -- To enlarge an order or rule (Law), to extend the time for complying with it. Abbott. -- To enlarge one's self, to give free vent to speech; to spread out discourse. "They enlarged th…

ibe a straight line when the wheel rolls around inside a fixed internal gear of twice its diameter.

Having wheels of the same size or diameter; having equal rotation. [R.]

An instrument for measuring the diameters of minute particles or fibers, from the size of the colored rings produced by the diffraction of the light in which the objects are viewed.

, a bit or drill made adjustable for holes of various sizes; one which can be expanded in diameter while boring. -- Expanding pulley (Mach.), a pulley so made, as in sections, that its diameter can be increased or diminished.

f the body. -- Fiddle block (Naut.), a long tackle block having two sheaves of different diameters in the same plane, instead of side by side as in a common double block. Knight. -- Fiddle bow, fiddlestick. -- Fiddle fish (Zoöl.), the angel fish. -- Fiddle head, an ornament on a ship's bow, curved like the volute o…