Cobalt
Cobalt names 4 different subjects across the 6 encyclopedias on this shelf. Each is set out below.
Cobalt This substance bears in many respects a close resemblance to nickel
The Encyclopedia of Founding (1892)
This substance bears in many respects a close resemblance to nickel, and is often found associated in nature with that metal. It is white, brittle, and tenacious, having a high melting-point; specific gravity, 8.5. Its principal ores are white cobalt, consisting of cobalt 44, arsenic 55, sulphur 0.50. All the ores of cobalt contain more or less nickel. See ARSENIC; NICKEL. Cohesion is that power by which the particles of bodies are held together. The absolute cohesion of solids is measured by the force necessary to tear them asunder. See TENACITY; STRENGTH OF MATERIALS. Coke is the residue resulting from the destructive distillation of soft or bituminous coal, and may be classed as an impure sub-variety of carbon, which, from a chemical point of view, may be classed either with graphite or charcoal, or perhaps between the two. It is made in ovens or in heaps, where the volatile matters are expelled, leaving the coke we use for melting purpose. About 2240 pounds of bituminous coal is required to produce from 1000 to 1400 pounds of good dry coke. The manufacture of illuminating gas necessitated the use of retorts, into which bituminous coal principally is charged and heated to redness by an external fire. At a moderate heat tar and oil are produced, but at a high temperature gases are formed in large quantities. The principal products of this destructive distillation are coal-tar, steam, ammonia, sulphide of hydrogen, carbonic acid, carburetted hydrogen, olefiant gas, and a solid, friable, carbonaceous mass, which is known as gas-coke. Coke specially manufactured for smelting purposes, of a good quality, is far superior to any kind of coal for melting in the cupola, as it melts faster and produces hotter iron. The best qualities are distinguished by their hardness, emitting a ringing sound when struck; a freedom from what is called smut, this being only partially burned at such parts--exposing a dark gray, fine cellular mass when fractured, with a silvery gloss overspreading the whole outer surface. The specific gravity of coke is 1.000; one cubic foot weighs 62 1/2 pounds, and the space required to stow one ton is 72 cubic feet. See COAL.
Cobalt a metallic element
Collier's New Encyclopedia (1921)
a metallic element, at. wt. 59, symbol Co. The metal was first obtained in an impure state by Brandt, in 1733. It occurs as speiss cobalt, or tinwhite cobalt CoAs2, and cobalt-glance, CoAsS. Cobalt occurs in meteoric iron. Metallic cobalt is a hard, magnetic, duetile, reddish-gray metal, with a high melting point. Its sp. gr. is 8.9. It is not easily oxidized by the air, when pure. It is dissolved by dilute HCl or H2SO4 with evolution of hydrogen . Cobalt forms two oxides: Cobaltous oxide CoO and Cobaltic oxide Co2O3. The alloys of cobalt are unimportant. Zaffre is an impure oxide of cobalt prepared by roastinsandal malt prepared by fusing ing cobalt ores with twice their weight partially roasted cobalt ores with a mixture of powdered quartz and potassium carbonate; while hot it is poured into water and and then ground to a fine powder; it is used as a pigment ; this color was known to the ancients. The cobaltous salts are the most stable in which cobalt acts as a dyad element. Cobalt compounds give a blue color to a borax bead. There is no native cobalt known, but many ores of the metal. Arsenate or Arseniate of Cobalt Erythrite ; Arsenical Cobalt Smaltite; Black Cobalt Asbolite; Bright-white Cobalt= Oobalt-glance; Carbonate of Cobalt = Remingtonite; Earthy Cobalt Asbolite; Gray Cobalt= Smaltite; Red Cobalt = Erythrite; Sulphate of Cobalt Bieberite ; Sulphuret of Cobalt Syepoorite, Linnæite; White Cobalt=Smaltite; Cobalt and Lead Selenite Tilkerodite. Ammonia cobaltous salts are formed by the union of cobaltous salts with ammonia in excess, the air being excluded , as, CoCl2.6NH3, rosecolored crystals. They are formed when an ammoniacal solution of cobalt is exposed to the air .
Cobalt a metal resembling silver in appearance
Aiton's Encyclopedia (1910)
a metal resembling silver in appearance; but with a slight trace of red. It is brittle and highly magnetic. It is harder than iron, but melts more easily and is a trifle heavier. Cobalt occurs in nature almost always in company with nickel, and is produced with it. Compounds of cobalt, called cobalt salts, have a peculiar way of changing color. When dry they are blue, and when wet they are red. Ink made of a cobalt salt is accordingly red, and produces red writing; but if the writing be dried before a fire until it loses its moisture, the writing turns blue. Exposure to vapor brings back a red color. If the ink be made very weak the red will not show, but heat will develop the blue. In this way secret correspondence has not infrequently been carried on. A letter in ordinary ink is sent with a second letter in invisible ink written between lines. Servants and spies not in the secret were satisfied with reading the letter written in black ink; while that written in sympathetic was unsuspected, save by the person for whom it was intended. Cobalt is a fast mineral dye, giving its name to cobalt blue. It is used in the manufacture of stained glass, paints, colored porcelain, etc. Cobalt blue is unrivaled for beauty and intensity. Large deposits of cobalt have recently been discovered in Canada. The output for 1909 was 48,000 tons, valued at $18,700,000. See Ink
Cobalt a city of Ontario
Collier's New Encyclopedia (1921)
a city of Ontario, Canada, in the Timiskaming district . It is on the Timiskaming and Northern Ontario railway and is the center of a rich mineral region, including mines of silver, nickel, bismuth, cobalt, copper, lead, and zinc. These deposits were first discovered in 1903. The silver mines were especially rich and their discovery resulted in a rush to the locality by by a large number of people, and the rapid development of the mines. The town grew rapidly, but in 1912 a large part of it was destroyed by fire. It was, however, rebuilt. Pop. about 6,000.
What Has Changed in the Last Century
Collier's flatly stated in 1921 that "the alloys of cobalt are unimportant" — the one sentence that has aged worst. Cobalt now goes into Alnico and samarium-cobalt permanent magnets, cemented-carbide tooling, the superalloys that let jet-engine turbine blades run near their melting point, and above all the lithium cobalt oxide cathodes of rechargeable batteries commercialised from 1991. The element also turned out to be biologically essential: cobalt sits at the centre of vitamin B12, whose structure was worked out in the 1950s, and the artificial isotope cobalt-60 became a workhorse of cancer radiotherapy and food and equipment sterilisation. Geography shifted too — Aiton's 1910 note of "large deposits recently discovered in Canada" has given way to the Democratic Republic of the Congo as the dominant source, with artisanal and child labour in its mines now a standing international controversy, while Cobalt, Ontario, the boom camp Collier's described, shrank to a village of about a thousand people.
Written for this edition, 2026.