specific purposes and to the identification of their generally applied trade names with those purposes.

The characteristic action of the saw being the removal successively of minute portions of the material worked by the cutting or tearing action of a series of sharp edges thrust against the material indicates that it is essentially a tool adapted for cross-cutting or cutting at right angles to the fibre of the material. Necessity and custom, however, have compelled its application for ripping or cutting with the grain also, thus adapting it to work which otherwise would be accomplished by the use of cutting tools such as axes and chisels. These conditions define two primary classes of saws the cross-cut saws and the rip-saws which divide all the dif

Uniform

335

of a tooth or the angle of the face of a tooth measured from a vertical line drawn through its point.

Gullet.- The depth of the tooth from the point to the root-line, the throat. Also the concave space at the back of a tooth.

Gauge. The thickness of the blade, usually measured by the wire gauge.

Set. The amount of lateral inclination

A

C

FIG. 3.

given to the teeth, either to the right or to the left of the plane of the blade, in order to produce a kerf or cut of sufficient width to effect a proper clearance of the sawdust and to prevent the saw from binding or being pinched by the sides of the cut.

Fleam. The side angle of a tooth.

Points. The number of teeth points to an inch. The coarseness and fineness of saws are usually estimated by the number of points instead of the number of teeth to an inch, and it should be observed that there is always one less tooth per inch than there are points. (See Fig. 1, Diag. B).

The several parts of a saw-tooth are usually described by the following terms: (See Fig. 1, Diag. A).

saw-teeth; in another sense the outer cutting extremity.

Saw-teeth vary in spacing, length or depth of gullet, angle, pitch, set, fleam and form of

Skewback Rip Saw

FIG. 5.

gullet. The teeth may be uniform throughout, or the blade may have several different kinds of teeth. In the latter case all the teeth of a kind are made uniform, or they are arranged in a regular order of change. (See Fig. 2).

The "angle" of a saw-tooth is that which is included in its point between the face and the back. The generic angle is 60 degrees, but it varies in the different kinds of teeth from 45 degrees to 70 degrees, according to the character of the material worked and the specific purpose for which the saw is used. The angle suitable for cutting soft wood and for ripping purposes is always more acute than that used for cutting hard wood and for cross-cutting. For soft wood, the front angle varies from 65 dergees to 70 degrees; for hard wood

FIG. 6.

from 80 degrees to 85 degrees. In saws employed for cutting very hard knotty wood, and in those used for cutting metal, the teeth are arranged in a series of equilateral triangles, the pitch of each tooth being evenly divided between the front and the back. In saws used for a general line of work, the angle usually adopted is 40 degrees, with the pitch evenly divided. In saws used for cutting soft woods and for ripping purposes, an effective placing of the angle is attained by making the face upright, and sloping the back. (See Fig. 3, Diags. A, B. C, respectively). The pitch of a saw tooth is obtained by subtracting the back angle from the front angle. These terms and rules apply generally to all the different kinds

B

A

C

FIG. 7.

of saws from the smallest hand and machine saws used by jewelers, machinists and carpenters, to the largest power-driven saws employed in the various classes of saw mills.

The various kinds of saws manufactured and used at the present time are of the following named general types:

The rip-saw, the hand-saw and the panelsaw. (See Fig. 4).

The carpenter's hand-saw for miscellaneous work is usually made from 20 to 30 inches in length, and is used for the common work of sawing material of moderate thickness both longitudinally and crosswise. The rip-saw and the panel-saw are modifications of the handsaw, from which they differ in the size of the teeth, and in the length of the blade. The ripA

saws range from 28 to 36 inches in length, and the panel-saws from 12 to 24 inches. The usual spacing of the teeth of the three types is as follows: Hand-saws, 5 to 12 points per inch; rip-saws, three to five points at the heel or handle end, and six to eight points per inch at the point; and the panel-saws, 8 to 12 points to the inch. All three forms are made with a straight upper edge, or a "skewback" curve as shown in Fig. 5. A novel and useful form is represented by the "combination" saws. These are graduated along the upper edge, and sometimes furnished with a level attachment as

shown in Diag. A, Fig. 7. Other useful modifications of the hand-saw are the gauge-saw, the ship-carpenter's saw, and the movable-back saw, shown by Diags. A, B, C, respectively, of Fig. 7. The gauge-saw is equipped with a movable attachment by means of which it may be adapted to tenoning, shouldering, curving, cog-cutting or to any other purpose where a definite depth of cut is required. The movable-back saw combines the advantages of a thin-bladed hand-saw and a first class back-saw. The ship-carpenter's saw has a very long narrow blade and is especially suitable for cutting sweeps or curves of long radius. It is handled like the rip-saw, and is extensively used by cabinet-makers, patternmakers and others for work requiring a narrow

curves and sweeps by hand and are sometimes called table-saws. The regular keyhole-saw and its modification, the pad-saw, are simply smaller forms of compass-saws, and are used for cutting curves of small radius, such as keyholes and other small holes in the central

FIG. 10.

portions of work. A saw of this type consists of a narrow blade which slides into a hollow handle or pad, to which it is secured in place by one or more set screws, only so much of the blade being drawn out as may be required by the character of the work. These saws are made both simply and in "nests." A nest of

Α

B

FIG. 11.

saws consists of a handle and three interchangeable blades, one each of the keyhole or pad, the compass and the table or pruning-saws. (See Fig. 9, Diag. A). A very useful novelty in this line is the nest of saws designed for cutting square holes. In this combination, the keyhole and compass blades are fitted with an attach

337

last named has the thinnest blade, so thin that simple filing gives the teeth sufficient set. The blades of the others are somewhat thicker and require a slight amount of set. All back-saws are best used in a mitre box or in some other form of guide rest. In cutting, they should be held firmly with the least practicable expenditure of force in controlling their direction, and the cut should be commenced by placing the heel of the blade on the farthest edge of the work and then drawing the saw steadily toward the body of the operator. Back-saw blades range from 8 to 18 inches in length,

FIG. 13.

the number of teeth varying in number from 10 to 14 per inch.

The pruning-saws are of several kinds, the principal forms of which are shown in Fig. 11. They vary from a large form of compass saw to straight saws toothed on both edges as shown in Diag. A, and also to those with curved blades as shown in Diag. B, a form extensively used on the Pacific Coast. They are also made of narrow blades attached to metal frames, the shape of which produce a tapered combination which permits of the use of the saw in very narrow spaces. See Fig. 11, Diag. C.

The construction of the tapered pruning-saw places it on the dividing line between what may be termed the regular bladed saw and the frame saw. In the former, the pressure on the cutting edge is resisted by the rigidity of the blade itself, while in the latter the pressure is resisted by the distribution of the tension of the blade through the various parts of the frame. Of the frame saws, the most familiar are the wood-saws shown in Fig. 12, the butchers' saws shown in Fig. 13 and the hack-saws shown in Fig. 14. The last named is shown in its adjustable and extendable form, in which the frame may be lengthened or shortened to fit blades of varying length. The saw has a thin, narrow blade and equilateral triangular-shaped teeth. It is stretched between the upright portions of a wrought-iron or steel frame, the

Round Breast Blade-for Hard Wood.

Straight Blade-Cross-cut teeth-Hd.or Sit.wd.

Straight Blade-Rip teeth-for Soft Wood

FIG. 12.

ment at right angles to the plane of the blade as shown at (C) Diag. B, Fig. 9.

The back-saws are a class of hand-saws characterized by deep thin blades stiffened with a metallic back as shown in Fig. 10. The principal forms are the mitre-box saw, the tenonsaw, the sash-saw and the dovetail-saw. The

VOL. 24-22

FIG. 14.

requisite tension being imparted by means of a thumb-screw at the forward end. A handle is attached to the back end of the frame, which is usually grasped by the right hand of the operator, and the downward pressure imparted to the tool during the act of cutting by laying the left hand upon the back or top of the frame. This saw is extensively used by fitters and mechanics for cutting odds and ends of metal, and has now become one of the most important tools in a machinist's toolbox. For general work, the blades are made with 14 teeth to the inch, but those used for cutting tubing and thin metal are

usually made with a greater number of teeth, about 25 per inch, in order to prevent a free bite and to reduce the danger of stripping the teeth. As in the case of the file, the fineness of the bite depends upon the number of the teeth in contact with the work; therefore, the judgment of the operator usually determines the amount of pressure that should be applied to the saw to suit the varying conditions of the cut. As in the case of other cutting tools, experience teaches that a hack-saw will work more effectively under a pressure sufficient to make the tool bite freely, than when it is allowed to scrape and glaze the surface under a light pressure. In order to use a hack-saw properly, the blade should be strained in the frame to prevent its kinking, and the cutting strokes should be made uniformly at a rate not exceeding 40 per minute. The blades should

FIG. 15.

be as short as possible, so as to reduce the cost and the danger of breakage, and oil should never be used on the teeth as it decreases their cutting efficiency. The reverse is true in the case of wood-working saws. Hack-saw blades as regularly manufactured range from 6 to 18 inches in length. Those longer than eight inches for hand-saws and 12 inches for powerdriven saws are seldom required. The railsaw is a modification of the hack-saw, the height of the frame being increased to adapt it for large work, such as the cutting off of rails, large beams, girders, etc., and is found to be a very valuable tool for contractors. The frames are fitted to carry blades ranging from 9 to 18 inches in length.

The cross-cut saws employed for cutting timber and other large work are made in an

Loup Handle

almost innumerable variety of forms and sizes both as to the blades and to the teeth. The "one man" saws, shown in Fig. 15, range from three to six feet in length. The particular saw illustrated has the famous "Great American" tooth, commonly known as the M tooth. Fig. 16 shows three forms of the larger saws. They range from 4 to 10 feet in length and are operated by two men, one at each handle. They are made with either curved or straight backs, but are always round-breasted, and differ in this respect from the drag- and pit-saws, in which the toothed edge is always straight.

Other saw terms are defined as follows: Arbor, the shaft, spindle or mandrel of a circular saw; crown-saw, the end of a cylinder having saw teeth arranged to cut out a round hole, called also a cylinder- or drum-saw; jump-saw, a circular saw made adjustable in up-and-down position; razor-saw, a hardened steel toothless wheel made thin for cutting stone, etc.; ring-saw, a band-saw set on guides to operate in a ring or circle; saw-back, the stiffening piece on the back of a band-saw; saw-bench, a bench fitted with guides, gauges, stops, clamps, fences, etc., for supporting and guiding work to be sawed; saw-gate, a frame in which gang-saws are set to stiffen them and prevent buckling, a similar device is termed a saw-hanging; saw-jointer, a mechanism for holding in position the blades of gang-saws while they are filed and set; saw-jumper, a device for spreading or setting saw-teeth; sawtable, the level surface on which the work is fed to a circular or band-saw that cuts through a gap in the table; saw-wrest, levered device for straining a saw-blade in giving the teeth a spring-set. The saw industry of the United States is mainly confined to about 100 factories, having 4,500 employees. In 1914 these produced a gross value of $12,517,000, but more than half of this was the value of the steel and other materials used. The industry about doubled its production between 1899 and 1914. Illinois is

the leading State, followed by New York. See WOOD-WORKING MACHINERY; LUMBER INDUSTRY IN THE UNITED STATES.

SAWYER, sâ'yer, SIR James, English physician: b. Carlisle, Cumberland, 11 Aug. 1844. He was educated at Queen's College, Birmingham, and at the London University. He is consulting physician to the Queen's Hospital at Birmingham, has held the chairs of pathology (1875-78), materia medica (1878-85), and medicine (1885-91), at Queen's College, Birmingham, and is the author of several important medical works. Among them are 'Floating Kidney) (1883); Ether in Medication by the Skin (1890), and Causes and Cure of Insomnia (1904); Dietetics of Diabetics' (1904); Longevity' (1905); 'Maladies of the Heart (1908); Coprotasis) (1912), etc.

SAWYER, Leicester Ambrose, American clergyman and Biblical scholar: b. Pinckney, N. Y., 28 July 1807; d. 1898. He was educated at Hamilton College, studied at Princeton Theological Seminary, and in 1832 entered the Presbyterian ministry. After filling pastorates in New York and Connecticut, he became president of Central College, Ohio. In 1854 he withdrew from the Presbyterian denomination and joined the Congregationalists. He made a complete translation of the Bible, that of the New Testament being published in 1858, the prophetical books of the Old Testament in 1860 and some of the remaining books in 1864. In some respects he was a pioneer in modern Biblical criticism, having for one thing abandoned the doctrine of verbal inspiration. His works include 'Elements of Biblical Interpretation' (1836); Mental Philosophy) (1839); Organic Christianity, or the Church of God' (1854); 'The Reconstruction of Biblical Theories, or Biblical Science Improved (1862); and 'Final Theology (1879).

SAWYER, Sylvanus, American inventor: b. Templeton, Mass., 15 April 1822; d. Templeton, 25 Oct. 1895. His attention was early turned to invention, and in 1839 he engaged in business with his brother-in-law in Augusta, Me., and invented a steam-engine, a screw propeller and a car run by foot-power. His first big invention, however, was the machine for making chair-cane from rattan, first invented in 1843 and used in his factories after 1850. Sawyer then turned his attention to gun and rifle projectiles and made important inventions, his projectiles making the rifled cannon a practicality. He also invented in 1853 an arrangement by which shells would explode on impact, by use of percussion caps. These inventions were put into use and did great service against the Confederacy in the ensuing war. Other inventions, after the war, perfected the cast-steel rifled guns, the first battery of which he furnished. His other inventions include calipers and dividers, steam generator, sole sewingmachine, centring watchmaker's lathe.

SAWYER, Thomas Jefferson, American Universalist clergyman: b. Reading, Vt., 9 Jan. 1804; d. 1899. He was graduated at Middlebury College in 1829, and held pastorates in New York (1830-45 and 1852-61). Between these periods he served as principal of the Liberal Institute at Clinton, N. Y., in which he also taught theology. He was one of the founders

339

of Tufts College, Medford, Mass., where he became professor of theology. As an advocate of Universalist doctrine and as a scholarly controversialist he acquired a wide reputation. His discussion with Isaac Westcott was published under the title of "The Doctrine of Eternal Salvation (1854). He also published Who is Our God? the Son or the Father?' (1859), in which he controverted in particular some of the opinions at that period held by Henry Ward Beecher.

SAXE, săks, John Godfrey, American poet: b. Highgate, Vt., 2 June 1816; d. Albany, N. Y., 31 March 1887. He was graduated at Middlebury College and admitted to the bar in 1843. During 1850-56 he conducted the Sentinel at Burlington, Vt., and in 1856 became attorneygeneral of Vermont and deputy collector of customs. Removing to Albany, N. Y., he edited the Evening Journal. He was a conspicuous figure on the lecture platform and at scholastic anniversaries, where he often read his verse. His reputation as a humorous poet was considerable during the mid-century, his verses often appearing in Harper's Magazine and in the Knickerbocker. He published 'Progress, a Satirical Poem) (1846); Humorous and Satirical Poems (1850); The Money King and Other Poems (1859); The Masquerade and Other Poems' (1866); (Fables and Legends of Many Countries (1872), and Leisure Day Rhymes (1875).

SAXE, Maurice, marshal of France: b. Dresden, 28 Oct. 1696; d. Chambord, near Blois, France, 30 Nov. 1750. He was a natural son of Augustus II of Poland. His military career was begun at the age of 12, and a few years later he was put in command of a cavalry regiment which took part in the war with Sweden. After the Treaty of Utrecht he attached himself to the army of France, and in 1720 was made camp marshal to the Duke of Orléans. He was offered the command of the Saxon army at the death of his father but chose to remain in the French service. For his defense of Alsace in 1743 he was created marshal of France. Carlyle has described his heroic conduct in the battle of Fontenoy, in his life of Frederick the Great. He was one of the most fearless but also one of the most dissolute men of his day. He wrote with a singular disregard of the rules of orthography a book on the art of war, entitled, 'Mes Rêveries.' Consult Weber, Karl von, Moritz von Sachsen' (1863); Duc de Broglie, Maurice de Saxe et le Marquis d'Argenson (1891-93).

SAXE-ALTENBURG, săks ǎl'ten-berg.

See ALTENBURG.

SAXE-COBURG-GOTHA, kō'berg gō'tą, Germany, comprising the provinces of Gotha and Coburg, constitutes one of the central states of the republic, containing an area of 764 square miles. It lies on the south side of the forest of Thuringia. Its principal rivers are the Apfelstedt, Gera, Leina-Horsel, Nesse and Unstrut, in Gotha, and the Itz, Rodach, Lauter and Steinach, in Coburg. Both parts are mountainous with undulating and fertile tracts. The highest summits are the Great Beerberg (2,850 feet), the Schneekopf (2,829), and the Inselberg (2,655). The government is a constitutional monarchy. The educational institu