Besides, for many purposes such forgings do not require tooling at
all, or only superficial grinding, while anvil-made ones would, in
consequence of their slight inaccuracies.
 |
| Fig. 19. |
Yet again, die forging is a very elastic system, and herein lies much of its value. Though it reaches its highest development when thousands of similar pieces are wanted, it is also adaptable to a hundred, or even to a dozen, similar forgings. In such cases economy is secured by using dies of a very cheap character; or, by employing such dies as supplementary to anvil work for effecting neat finish to more precise dimensions than can be ensured at the anvil. In the first case use is made of dies of cast iron moulded from patterns (fig. 19) instead of having their matrices laboriously cut in steel with drills, chisels and milling tools. In the second, preliminary drawing down is done under the steam hammer, and bending and welding at the anvil, or under the steam hammer, until the forgings are brought approximately to their final shape and dimensions. Then they are reheated and inserted in the dies, when a few blows under the steam or drop hammer suffice to impart a neat and accurate finish.
The limitations of die forging are chiefly those due to large dimensions. The system is most successful for the smallest forgings and dies which can be handled by one man without the assistance of cranes; and massive forgings are not required in such large numbers as are those of small dimensions. But there are many large articles manufactured which do not strictly come under the term forgings, in which the aid of dies actuated by powerful hydraulic presses is utilized. These include work that is bent, drawn and shaped from steel plate, of which the fittings of railway wagons constitute by far the largest proportion. The dies used for some of these are massive, and a single squeeze from the ram of the hydraulic press employed bends the steel plate between the dies to shape at once. Fairly massive forgings are also produced in these presses.
Die forging in its highest developments invades the craft of the skilled smith. In shops where it is adopted entirely, the only craftsmen required are the few who have general charge of the shops. The men who attend to the machines are not smiths, but unskilled helpers. (J. G. H.)
FORK (Lat. furca), an implement formed of two or more
prongs at the end of a shaft or handle, the most familiar type
of which is the table-fork for use in eating. In agriculture and
horticulture the fork is used for pitching hay, and other green
crops, manure, &c.; commonly this has two prongs, “tines”;
for digging, breaking up surface soil, preparing for hand weeding
and for planting the three-pronged fork is used. The word is
also applied to many objects which are characterized by branching
ends, as the tuning-fork, with two branching metal prongs,
which on being struck vibrates and gives a musical note, used to
give a standard of pitch; to the branching into two streams
of a river, or the junction where a tributary runs into the main
river; and in the human body, to that part where the legs
branch off from the trunk.
The furca, two pieces of wood fastened together in the form of the letter Λ, was used by the Romans as an instrument of punishment. It was placed over the shoulders of the criminal, and his hands were fastened to it, condemned slaves were compelled to carry it about with them, and those sentenced to be flogged would be tied to it; crucifixions were sometimes carried out on a similar shaped instrument. From the great defeat of the Romans by the Samnites at the battle of the Caudine Forks (Furculae Caudinae), a narrow gorge, where the vanquished were compelled to pass under the yoke (jugum), as a sign of submission, the expression “to pass through or under the forks” has been loosely used of such a disgraceful surrender. The “forks” in any allusion to this defeat should refer to the topographical name and not to the jugum, which consisted of two upright spears with a third placed transversely as a cross-bar.
FORKEL, JOHANN NIKOLAUS (1749–1818), German
musician, was born on the 22nd of February 1749 at Meeder
in Coburg. He was the son of a cobbler, and as a practical
musician, especially as a pianoforte player, achieved some
eminence; but his claims to a more abiding name rest chiefly
upon his literary skill and deep research as an historian of musical
science and literature. He was an enthusiastic admirer of J. S.
Bach, whose music he did much to popularize. His library,
which was accumulated with care and discrimination at a time
when rare books were cheap, forms a valuable portion of the
royal library in Berlin and also of the library of the Königlicher
Institut für Kirchenmusik. He was organist to the university
church of Göttingen, obtained the degree of doctor of philosophy,
and in 1778 became musical director of the university. He died
at Göttingen on the 20th of March 1818. The following is a list
of his principal works: Über die Theorie der Musik (Göttingen,
1777); Musikalisch kritische Bibliothek (Gotha, 1778); Allgemeine
Geschichte der Musik (Leipzig, 1788). The last is his most important
work. He also wrote a Dictionary of Musical Literature,
which is full of valuable material. To his musical compositions,
which are numerous, little interest is to-day to be attached.
But it is worth noting that he wrote variations on the English
national anthem “God save the king” for the clavichord, and
that Abt Vogler wrote a sharp criticism on them, which appeared
at Frankfort in 1793 together with a set of variations as he
conceived they ought to be written.
FORLÌ (anc. Forum Livii), a town and episcopal see of Emilia,
Italy, the capital of the province of Forlì, 40 m. S.E. of Bologna
by rail, 108 ft. above sea-level. Pop. (1901) 15,461 (town);
43,321 (commune). Forlì is situated on the railway between
Bologna and Rimini. It is connected by steam tramways with
Ravenna and Meldola, and by a road through the Apennines
with Pontassieve. The church of S. Mercuriale stands in the
principal square, and contains, besides paintings, some good
carved and inlaid choir stalls by Alessandro dei Bigni. The
façade has been considerably altered, but the campanile, erected
in 1178–1180, still exists; it is 252 ft. in height, square and built
of brickwork, and is one of the finest of Lombard campanili.
The pictures in this church are the work of Marco Palmezzano
(1456–1537) and others; S. Biagio and the municipal picture
gallery also contain works by him. The latter has other interesting
pictures, including a fresco representing an apprentice with
pestle and mortar (Pestapepe), the only authentic work in Forlì
of Melozzo da Forlì (1438–1494), an eminent master whose style
was formed under the influence of Piero della Francesca, and
who was the master of Palmezzano; the frescoes in the Sforza
chapel in SS. Biagio e Girolamo are from the former’s designs,
though executed by the latter. The church also contains the
fine tomb (1466) of Barbara Manfredi. The cathedral (Santa
Croce) has been almost entirely rebuilt since 1844. The Palazzo
del Podestà, now a private house, is a brick building of the 15th
century. The citadel (Rocca Ravaldina), constructed about
1360–1370, and later rebuilt, is now used as a prison. Flavio
Biondo, the first Renaissance writer on the topography of ancient
Rome (1388–1463), was a native of Forlì.
Of the ancient Forum Livii, which lay on the Via Aemilia, hardly anything is known. In the 12th century we find Forlì in league with Ravenna, and in the 13th the imperial count of the province of Romagna resided there. In 1275 Forlì defeated Bologna with great loss. Martin IV. sent an army to besiege it in 1282, which was driven out after severe fighting in the streets; but the town soon afterwards surrendered. In the 14th and 15th centuries it was under the government of the Ordelaffi; and in 1500 was taken by Caesar Borgia, despite a determined resistance by Caterina Sforza, widow of Girolamo Riario. Forlì finally became a part of the papal state in 1504. (T. As.)
FORLIMPOPOLI (anc. Forum Popillii), a village of Emilia,
Italy, in the province of Forlì, from which it is 5 m. S.E. by rail,
105 ft. above sea-level. Pop. (1901) 2299 (town); 5795 (commune).
The ancient Forum Popillii, a station on the Via Aemilia,
was destroyed by Grimuald in 672. Whether its site is occupied
by the present town is not certain; the former should perhaps
be sought a mile or so farther to the S.E., where were found most
of the inscriptions of which the place of discovery is certain.
Forlimpopoli was again destroyed by Cardinal Albornoz in 1360,
and rebuilt by Sinibaldo Ordelaffi, who constructed the well-preserved
medieval castle (1380), rectangular with four circular
towers at the corners.
(T. As.)
FORLORN HOPE (through Dutch verloren hoop, from Ger.
verlorene Haufe = “lost troop”; Haufe, “heap,” being equivalent
in the 17th century to “body of troops”; the French
