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Z.
Zam-pog′na.
The Italian bagpipes; probably allied to the
sumphonia, of the
Book of
Daniel, in the Hebrew version.
It was probably a syrinx with bellows, the original type of the organ.
The bagpipes in the
tibia utricularis of the Romans.
See bagpipes.
Zawn.
（
Mining.) A cavern.
Zax.
A slater's hatchet, with a sharp point on the pole, for perforating the slate to receive the pin.
Sax; saixe.
The zax is about 16 inches long and 2 in width; it is somewhat bent at one end, and the spur is 3 inches long.
Ze′nith-sec′tor.
Invented by
Hooke, about 1699, to ascertain whether or no the earth's orbit had any sensible parallax.
As modified by Airy, it is principally used in geodetical operations.
It serves to determine the zenith point and the zenith distances of stars.
Ze′nith-tel′e-scope.
A geodetical instrument, invented by
Captain Talcott, United States Engineer, for measuring the difference of the zenith of two stars, as a means of determining the latitude.
Two stars are selected which pass the meridian about the same time and at about equal distances from the zenith, but on opposite sides of it. It has adjustments in altitude and azimuth, has a graduated vertical semicircle and a level, and a micrometer for measuring the distances between the stars.
Ze′nith-tube.
Invented by Airy.
It is used at
Greenwich for stellar observations.
Zigzag.
1. (
Fortification.) One of the trenches leading toward the besieged works, and communicating between the several
parallels.
It turns to the right and to the left, but with a general curved course, in such a manner as not to be enfiladed by the guns of the fort.
The
approaches to
Sebastopol, including the
zigzags and
parallels, embraced 70 miles of sunken trenches, and required no less than 60,000 fascines, 80,000 gabions, and 1,000,000 sandbags, to protect the men working in the trenches and at the different batteries.
2. A winding chute on the face of a dam to enable fish to ascend.
A
salmon-stair; fishway; fish-ladder.
Zinc.
Equivalent, 32.5; symbol, Zn.; specific gravity, cast, about 6.8; rolled, 7 to 7.2; fusingpoint, 773° Fah.
A rather hard bluish-white metal, tough and not easily broken by blows of the hammer, in its ordinary state at common temperatures, but when heated to a point approaching that of fusion it becomes brittle.
At temperatures between 210° and 300° it is ductile and malleable, and may be rolled into thin sheets and drawn into moderately fine wire, which, however, possesses but little tenacity.
It preserves its malleability after rolling.
Sheet-zinc is largely used as a covering for roofs and for other purposes, and the metal is also used for coating iron, which is then commonly said to be
galvanized. For this purpose the iron is dipped into dilute sulphuric acid to remove scale, and then plunged into a bath of molten zinc, covered with sal-ammoniac.
Combined with copper it forms brass; with the addition of tin and other metals various similar alloys are formed, some of which are distinguished by specific names.
The prepared oxide is extensively used as a pigment, and the sulphate is the
white-vitriol of commerce.
It is not found native.
Its principal ores are the
red oxide; the carbonate, or calamine; the sulphide, or
blende, the dark varieties of which are termed
black-jack by the
English miners; and the silicate, which is usually found associated with the carbonate.
The metal itself was unknown to the Greeks,
Romans, and Arabians, and in fact in
Europe previous to about the middle of the sixteenth century, though it is said to have been used in
India and
China from an early period.
It is produced in
England,
France,
Belgium,
Germany, and in
New Jersey and
Pennsylvania.
The fact that certain ores yielded a yellow copper (brass) was early known, and the product was highly esteemed; but it was not understood that it was a true alloy, nor was zinc obtained distinctly.
This was partly owing to the fact that zinc vaporizes at a certain heat, and the sublimed portions which adhered to the sides of the furnace had no appearance of metal.
Mines yielding this gold-colored metal were highly esteemed, and when exhausted the fact was lamented; but in course of time it was discovered that the addition of a certain stone (calamine) to copper, when melting, gave it the desired yellow color.
This earth was used for the specific purpose, but it was long ere the truth was elicited that calamine was a metallic ore, and yielded its base to form an alloy with the copper.
See brass.
Aristotle,
Strabo, and various other writers refer to an earth which conferred a yellow color on copper.
Brass was considered a more valuable kind of copper.
Ambrosias,
Bishop of
Milan in the fourth century, Promasius,
Bishop of Adrumetum, in
Africa, in the sixth century, and Isidore,
Bishop of
Seville in the seventh century, mention an addition by which copper acquired a gold color.
This was, undoubtedly, calamine.
Albertus Magnus (1205-1280) speaks of calamine as a semimetal.
The
furnace-calamine, or sublimated zinc, with which the furnaces and chimneys were lined, where zinc-yielding ores were smelted, was thrown aside as useless until the middle of the sixteenth century.
It had a place in the pharmacopoeia, but this use required but a small portion of the quantity produced.
Erasmus Ebener, who died in 1577, used the furnace-calamine instead of native calamine for making brass.
This was introduced at Rammelsberg about 1557.
Its use in this connection had been previously described by
Albertus Magnus.
White vitriol, the sulphate of zinc, was long prepared, used, and employed before it was known that it was a salt of zinc.
It is said to have been first made by
Duke Julius at Rammelsberg, in 1570.
Its application to make an eye-water is its first recorded use.
The ore (calamine) whose effect on copper had been known for so many centuries is first described as a distinct metal by that brilliant absurdity Paracelsus (died 1541), and is called
zinc. He says:—
“There is another metal, zinc, which is in general unknown.
It is a distinct metal of a different origin, though adulterated with many other metals.
It can be melted, for it consists of three fluid principles, but it is not malleable.
In its color it is unlike all others, and does not grow in the same manner, but with its
ultima materia. I am as yet unacquainted, for it is almost as strange in its properties as argentum vivum” (quicksilver).
In the preparation of metallic zinc, as practiced in this country, by what is known as the Belgian method, the ore, having been broken and calcined, is mixed with 33 per cent of crushed coal, and the mass is distributed in charges of 27 pounds to retorts, of which there are 56 in each furnace, arranged in tiers.
The orifices of the retorts are cemented in conical tubes of fire-clay, projecting 18 inches beyond the sides of the furnace, and the interspaces sealed with fire-clay.
The furnace is then fired up until a heat of 2160° Fah. — the vaporizing point of zinc — is attained.
The carbon combines with the oxygen in the ore, and the metallic vapor is condensed into the liquid form by the projecting tubes, which have a temperature below that of the vaporizing point of the metal.
At intervals the molten metal is withdrawn from the retorts, by means of iron hooks or scrapers, and is received in large ladles, from which it is poured into iron molds, forming slabs weighing 30 pounds each.
The gases issuing from the orifices in the condensers during the process burn with the most vivid flames and varied colors.
Two charges are worked each day. While still hot, the slabs of zinc are taken from the molds and rolled into rough thick plates, 10 × 18 inches; from nine to twelve of these are placed in an iron box, and, the boxes being placed in a furnace, the pack of plates is removed from the furnace and the whole rolled out together, each plate forming a sheet, when trimmed, 7 feet long by 3 feet wide.
In making oxide of zinc, or
zinc-white, the carbonate and silicate of zinc, as they come from the mine, are crushed, mixed with 33 per cent of coal, and heated in large
fire-brick furnaces, provided with an air-blast, the oxygen from which combines with the metallic vapor as fast as it is liberated.
The oxide thus formed is conveyed by a blast into a shaft, whence the white flocculent vapor, which is contaminated with various impurities, is driven by blowers through a series of chambers connected by pipes.
The impurities are successively deposited, the purest vapors passing through pipes and being finally condensed, as an almost impalpable white powder, in muslin bags attached to the pipes.
It has been proposed to employ zinc for extracting gold from auriferous rocks.
The pulverized rock is gradually introduced into a bath of molten zinc, which combines with the precious metal, while the refuse rises to the top and can be skimmed off. The gold may be subsequently separated by distilling the alloy, the zinc passing over and leaving the precious metal behind.
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Zinc-sheets.
Thickness and Weight per square foot.
Inch.
.0311 = 10 ounces.
.0457 = 12 ounces.
.0534 = 14 ounces.
Inch.
.0611 = 16 ounces.
.0686 = 18 ounces.
.0761 = 20 ounces.
Zinc-cem′ent.
Soret's cement is formed by making oxide of zinc into a paste with a solution of chloride of zinc.
This paste quickly sets into a hard mass, which may be applied for stopping teeth and a variety of useful purposes.
Dr. Tollens gives a cheaper form of the same cement, which may be used for stopping cracks in metallic apparatus, and cementing glass,
crockery-ware, and other materials.
He mixes equal weights of commercial zincwhite and very fine sand, and makes the mixture into a paste with a solution of chloride of zinc, having the density 1.26.
The mixture sets rapidly, but allows plenty of time for its application.
As it resists the action of most agents, it is very useful in the chemist's laboratory.
Zinc-fur′nace.
The carbonate of zinc (
calamine) and the sulphuret of zinc (
blende) are smelted by mixing with charcoal in a crucible or retort, and then heating.
For the production of the white oxide a process of dry distillation is instituted, and the fumes of the metal are conducted off, condensed and collected for a pigment.
For the metal air is excluded from the chambers.
See zinc-white.
Benecke and Shear's zinc-furnace (
English) is intended for the distillation of zinc by the process following:—
The ores are roasted in the ordinary way, by stratifying them with fuel and setting fire to the pile.
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Zinc-furnace. |
The ore is then spread out in the air and lixiviated to remove the sulphate of zinc.
It is then dried, pulverized, roasted to extricate the sulphur, powdered, mixed with carbonaceous matters, and saturated with an alkaline lye.
The prepared ore is then placed in the fire-clay retorts
a, being introduced at the opening, which is afterward occupied by the neck of the head-piece
b.
d is an opening at which spent ores are removed, and is closed and luted during the firing.
A lengthening tube
c is added to the head-piece
b. The vapor which is sublimated from the ore becomes cooled in the head-piece
b, and is condensed upon an iron plate beneath.
This condensing-chamber is separated by partitions from those of the neighboring retorts, and all points of access are carefully luted.
The operation is observed by a glazed eye-hole.
The retorts are arranged in two ranks and heated by the fire between them.
See zinc-furnace patents:—
| No. | Name. |
| 91,051. | Thoma. |
| 91,052. | Thoma. |
| 46,198. | Webster. |
| 6,180. | Boyden. |
| 32,840. | Muller |
| 99,145. | Adams. |
| 145,450. | Richter. |
| 16,594. | Kent. |
| 17,333. | Mamier. |
| 25,267. | Kalbach. |
See also zinc-white.
Zin′code.
The positive pole of a galvanic battery.
Zinc-og′ra-phy.
The design is drawn on the zinc-plate with a material which resists acid.
The surface of the plate being
bit away leaves the design in relief to be printed from by the ordinary mode in printing from woodcuts.
The process does not appear to have made much headway since its introduction in 1816, though some beautiful specimens were made in
England more than thirty years back.
See Panicograph; Galvanograph; Galvano-plastic process.
Zinc-white.
Zinc-white (oxide of zinc; ZnO.) is a white powder obtained by the sublimation of the red oxide.
This is found in abundance at
Mount Sterling, N. J. It is pulverized, mixed with coal, heated in brick retorts, through which blasts of air are passed.
The oxygen of the air combines with the vapor of the zinc, and the flocculent oxide is carried off by the draft of air through tubes leading to a chamber where the
zinc-white falls in the shape of a fine powder.
Fig. 7394 shows the arrangements adopted in the preparation of zinc-white (oxide of zinc.) The several furnaces
a have openings in their tops, communicating with a common flue
c. The finely ground zinc ore, mixed with its bulk or more of fine anthracite coal, is charged into the furnaces, and the mass, when ignited, is fed with a blast of air from a pipe
b, affording the oxygen necessary for oxidation; the vapor passes through the chamber
d, which is provided with vertical partitions, extending from the top and bottom, where its progress is checked sufficiently to allow any ash and coal passing over to settle; it is withdrawn thence by the fan
f passing through the ascending and descending pipes
e, and forced into a second chamber, where it is cooled and farther purified.
It is thence distributed by downcast pipes
h among a series of horizontal and vertical flannel bags
j k l, in which it is condensed as a fine white powder; the lower bags receive that which is shaken into them from those above.
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Zinc-white apparatus. |
List of United States Patents for Zinc-White.
| No. | Name and Date. |
| 7,351. | Leclaire et al., May 7, 1850. |
| 8,308. | Seymour, August 26, 1851. |
| 8,477. | Adams, Oct. 28, 1851. |
| 8,756. | Jones, Feb. 24, 1852. |
| 10,574. | Renton, Feb. 28, 1854. |
| 10,696. | Jones, Mar. 28, 1854. |
| 10,711. | Trotter, Mar. 28, 1854. |
| 12,329. | Selleck, Jan. 30, 1855. |
| 12,333. | Trotter, Jan. 30, 1855. |
| 12,418. | Wetherell, Feb. 20, 1855. |
| 12,613. | Gardner, Mar. 27, 1855. |
| 13,332. | Jones, July 24, 1855. |
| 13,416. | Burrows,1 Aug. 14, 1855. |
| 13,431. | Jones, Aug. 14, 1855. |
| 13,806. | Wetherill, Nov. 13, 1855. |
| 15,448. | Wharton, July 29, 1856. |
| 15,830. | Wetherill, Sept. 30, 1856. |
| 16,594. | Kent, Feb. 10, 1857. |
| 20,655. | Monnier, June 22, 1858. |
| 20,926. | Wharton et al., July 13, 1858. |
| 27,142. | Millbank, Feb. 14, 1860. |
| 32,320. | Titterton,2 May 14, 1861. |
| 33,911. | Weissenborn, Dec. 10, 1861. |
| 36,414. | Lewis, Sept. 9, 1862. |
| 37,150. | Wharton, Dec. 16, 1862. |
| 38,493. | Lewis, May 12, 1863. |
| 43,587. | Jenkins et al., July 19, 1864. |
| 67,839. | Bartlett et al., Aug. 20, 1867. |
| 69,573. | Mills, Oct. 8, 1867. |
| 72,032. | Hall, Dec. 10, 1867. |
| 73,146. | Wetherill, Jan. 7, 1868. |
| 73,147. | Wetherill, Jan. 7, 1868. |
| 83,643. | Lees, Nov. 3, 1868. |
| 95,484. | Jones, Oct. 5, 1869. |
| 108,965. | Burrows, Nov. 8, 1870. |
| 138,684. | Osgood, May 6, 1873. |
| 136,685. | Osgood, May 6, 1873. |
| 139,701. | Bartlett, June 10, 1873. |
| 142,571. | Lang, Sept. 9, 1873. |
| 145,976. | Trotter, Dec. 30, 1873. |
See also
white-lead.
Zir-co′ni — a light.
One in which a stick of oxide of zirconium is exposed to the flame of oxyhydrogen gas. Invented by
Tessie du Motay.
It is said to be entirely unaltered by the heat, and to develop more intense light than any other terrous oxide.
Zir-co′ni-um.
A rare metal obtained from the minerals zircon and hyacinth by Berzelius in 1824.
Zith′ern.
An
Austrian musical instrument of the
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lute order.
It has twenty-eight strings, lies on the table or in the lap, and is played by both hands.
Zo′cle.
1. A low, plain, square member or plinth supporting a column.
2. A short pedestal; a footstool.
Socle.
Zo′e-trope.
This mechanical toy, like the
thaumatrope, which amused the preceding generation, depends for its interest upon the constancy of visual impressions.
See also Anorthoscope; Phenakis-Toscope; Stroboscope; Rotascope; etc.
It consists of a rotating drum, open at the top, in which, around its inner periphery, are placed strips of paper having figures of men, animals, etc., in varying positions.
By turning the cylinder, the images are seen through slots in its upper side, giving the effect of action to the figures.
For instance, a porpoise is represented in perhaps a dozen different positions.
The turning of the drum brings into view, in rapid succession, the varying positions of the fish until they blend into a perfect image full of motion, and operating to simulate the natural action of the animal.
A man sawing wood, an animal kicking, a clown jumping through a hoop, an acrobat playing with clubs, are thus shown in apparent motion.
It is described in a paper by
W. G. Horner, in the “Philosophical magazine,” January, 1834, “On the Properties of the
Daedaleum, a new Instrument of Optical Illusion.”
See also
Lincoln's patent, No. 64,117, April 23, 1807.
Its action depends upon the persistence of visual impressions.
It is a cylinder rotating on a vertical shaft, and having vertical slits in the sides, through which are viewed the pictures, which are on strips placed around the inside of the cylinder.
The vision is interrupted by the spaces between the embrasures, and the object consists of a figure or group, in a series of successive attitudes, which, viewed consecutively, without appreciable interval, appear as a single moving object.
Zo-oph′o-rus.
（
Architecture.) The
frieze; so called on account of the ornaments carved on it, among which are the figures of animals.
Zo′o-phyte-trough.
A device for retaining living zoophytes or infusoriae, which are to be examined under the microscope.
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Zoophyte-trough. |
The two sides are of glass, and it has a glass false bottom sufficiently narrow to admit the edges of two glass plates between it and the sides.
This is movable, so that one of the plates may be inserted on each side, forming a reservoir for the water containing the zoophytes.
The upper edges of the plates are pressed together by a spring, but may be separated as far as desired by a wedge.
Zu-mom′e-ter.
An instrument like a hydrometer, to show the condition of fermenting mash.
Zu-mo-sim′e-ter.
See Zumometer.
Zy-mom′e-ter.
A measurer of the degree of fermentation.
Zy-mo-sim′e-ter.
An instrument for detecting the condition and process of fermenting wort or mash.
Zymometer.
