limits of Scranton in 1788, and a primitive grist-mill, a saw-mill and a charcoal iron-furnace were erected during the next few years; but there was little further development until 1840, when the Lackawanna Iron Company was formed for the manufacture of iron here. The limestone and iron ore of the vicinity proved to be of inferior quality, and the failure of the enterprise was prevented only by the persistent efforts of George Whitefield Scranton (1811–1861), aided by his brother Selden T. Scranton and his cousin Joseph Hand Scranton. Under the leadership of George W. Scranton better grades of iron ore and of limestone were procured, and within a decade a rolling mill, a nail factory and a manufactory of steel rails were established, and adequate facilities for railway transportation were provided. Scranton was incorporated as a borough in 1854, was chartered as a city of the third class in 1866, and became a city of the second class in 1901. See B. H. Throop, A Half-Century in Scranton (Scranton, 1895).
SCREAMER, a bird inhabiting Guiana and the Amazon valley,
so called in 1781 by T. Pennant (Gen. Birds, p. 37) “from the
violent noise it makes”—the Palamedea cornuta of Linnaeus.
First made known in 1648 by G. de L. Marcgrav under the name
of “Anhima,” it was more fully described and better figured
by Buffon under that of Kamichi, still applied to it by French
writers. Of about the size of a turkey, it is remarkable for the
curious “horn” or slender caruncle, more than three inches
long, it bears on its crown, the two sharp spurs with which each
wing is armed, and its elongated toes. Its plumage is plain
in colour, being of an almost uniform greyish black above, the
space round the eyes and a ring round the neck being variegated
with white, and a patch of pale rufous appearing above the
carpal joint, while the lower parts of the body are white. Closely
related to this bird is another first described by Linnaeus as a
species of Parra (see Jaçaná), to which group it certainly does
not belong, but separated therefrom by Illiger to form the genus
Chauna, and now known as C. chavaria, very generally in English
as the “Crested Screamer,” a name which was first bestowed
on the Seriema (q.v.). This bird inhabits the lagoons and swamps
of Paraguay and Southern Brazil, where it is called “Chajá”
or “Chaka,” and is smaller than the preceding, wanting its
“horn,” but having its head furnished with a dependent crest
of feathers; while the plumage is grey. Its nest is a light construction
of dry rushes, having its foundation in the water, and
contains as many as six eggs, which are white tinged with buff.
The young are covered with down of a yellowish-brown colour.
A most singular habit possessed by this bird is that of rising
in the air and soaring there in circles at an immense altitude,
uttering at intervals the very loud cry of which its local name
is an imitation. From a dozen to a score may be seen at once
so occupying themselves. The young are often taken from the
nest and reared by the people to attend upon and defend their
poultry, a duty which is faithfully[1] and, owing to the spurs
with which the chaka’s wings are armed, successfully discharged.
Another very curious property of this bird, which was observed
by Jacquin, who brought it to the notice of Linnaeus,[2] is its
emphysematous condition—there being a layer of air-cells
between the skin and the muscles, so that on any part of the
body being pressed a crackling sound is heard. In Central
America occurs another species, C. derbiana, chiefly distinguished
by the darker colour of its plumage. For this a distinct genus,
Ischyrornis, was proposed, but apparently without necessity,
by A. B. Reichenbach (Syst. Avium. p. xxi.).
The taxonomic position of the Palamedeidae, for all will allow to the screamers the rank of a family at least, has been much debated. Their anserine relations were pointed out by W. K. Parker in the Zoological Proceedings for 1863 (pp. 511-518, and in the same work for 1867 T. H. Huxley placed the family among his Chenomorphae; but this view was contravened in 1876 by A. H. Garrod, who said, “The screamers must have sprung from the primary avian stock as an independent offshoot at much the same time as did most of the other important families.” P. L. Sclater in 1880 placed them in a distinct order, Palamedeae, which he, however, placed next to the true Anseres, and they are now generally regarded as forming a suborder of anseriform birds.
SCREEN (usually, but very doubtfully, connected with Lat.
scrinium, a box for holding books, from scribere, to write; a
connexion with Ger. Schranke, barrier, has been suggested), in
architecture, any construction subdividing one part of a building
from another—as a choir, chantry, chapel, &c. The earliest
screens are the low marble podia, shutting off the chorus cantantium
in the Roman basilicas, and the perforated cancelli
enclosing the bema, altar, and seats of the bishops and presbyters.
The chief screens in a church are those which enclose the choir
or the place where the breviary services are recited. This is done
on the continent of Europe, not only by doors and screen-work,
but also, when these are of open work, by curtains, the laity
having no part in these services. In England screens were of
two kinds: one of open woodwork; the other, massive enclosures
of stonework enriched with niches, tabernacles, canopies,
pinnacles, statues, crestings, &c., as at Canterbury, York,
Gloucester, and many other places both in England and abroad
(see Rood and Jubé).
As an article of furniture, the screen is an ornamental frame, usually of wood, but sometimes of metal, for protection from observation, draught, or the heat of a fire. Screens are made of all shapes and sizes, and may consist of leather, paper or textile materials fastened to the framework; they may have several leaves or only one—thus a fourfold screen has four leaves. Firescreens are usually small, with a single leaf—indeed in the Georgian period of English furniture they often took the form of a circular, oval, heart-shaped or oblong piece of framed embroidery fixed to a wooden pole or upright, upon which they could be raised or lowered. This variety, which was called a pole-screen, was more effective as an ornament than as a protection. The hand-screen was light and portable, as the name implies. At the present time fire-screens are often of glass set in metal frames. The larger type of screen, with several leaves, is of uncertain origin, but probably first came into use towards the end of the 16th century. The earlier examples were of stamped or painted Spanish leather or of some rich stuff such as tapestry; at a later date lacquer was extensively used. They were tall enough to conceal the person sitting behind them, and were frequently exceedingly handsome and stately.
SCREW (O.E. scrue, from O. Fr. escroue, mod. écrou; ultimate
origin uncertain; the word, or a similar one, appears in Teutonic
languages, cf. Ger. Schraube, Dan. skrue, but Skeat, following
Diaz, finds the origin in Lat. scrobs, a ditch, hole, particularly
used in Low Latin for the holes made by pigs boring in the
ground with their snouts), a cylindrical or conical piece of wood
or metal having a groove running spirally round it. The surface
thus formed constitutes an external or male screw, while a similar
groove cut round the interior of a cylindrical hole, as in a nut,
constitutes an internal or female screw. The ridge between
successive turns of the groove is the “thread,” and the distance
between successive turns of the thread is the “pitch.” The present
article will deal with the standard pitches in common use and
with modern methods of manufacture, the earlier history of which,
down to the time of Sir Joseph Whitworth, may be read in
Holtzapffel’s Turning and Mechanical Manipulation. For the
screw as a mechanical power see Mechanics; for the screw
used to propel steamships see Shipbuilding.
Standardization of Screws.—All screws made to-day are copies of pre-existing or master screws, which are familiarly known as “guide screws,” “hobs” or “leaders,” “chasers” or “comb tools,” “taps,” and “dies” in numerous forms. These are so standardized that a thread cut to a given standard in England fits its fellow thread cut to the same standard in America, Germany or elsewhere. At one time screws cut by one firm would not match those cut by another. Formerly there was no “tackle,” but large screws were cut with chisel and file, and a nut was cast around them and used for correction, until gradually
