United States Treasury Department, adapted to give
several series of lines, thereby forming a network.
The usual form of medallion-maehine is cited on
pages 1417, l-US, and need nut be re-described.
Speaking in the most general terms, a tracer is made
to follow the contour of the relief on the
medal, and governs the motions of the
diamond scriber wliich moves over the C^
plate to be engraved, the ascents and de
scents of the tracer resolving themselves into devia
tions from the straight line on the engraved plate,
the tracer and scriber being connected, and moved
simultaneously over their respective surfaces, and
being set forward a given and eipial distance be I
tween each stroke.
In Casilear and Smith's medallion ruling-ma
chine, for ruling t\vo or more lines, there are
two right-angle slides crossing at 2'2i°, each
slide with a screw and inde.'C, to give the proper
width of line to the ruling. The medallion and
plate to be ruled are placed on the talile of the
top slide : in ruling the cross lines, the move-
ment is given either at the angles of 221°, 45°,
or 67i°. The selection of the angle determines
the form of mesh of the network produced, wliether
sijuare or lozenge. The (lortrait (Plate LXVII.) is
the production of this machine.
The border around the portrait is the production
of the rose-engine, or geometric lathe, described on
pages 1983, I'JSf, and 963. The action of the cut-
ting-tool in the rose-engine is to make lines the
product of a cond)ination of motions of the bed-]date,
and the possible variations are almost infinite. Plate
LXIV., SrKEL-EXGii.vvrs'i:, shows a number of speci-
mens of its work : the oruamental panel behind the
lettei-s "Washington"; the oval immediately above
the work on the upright sides of the border. Plate
LXIV. is printed, not as a S(«;/rtfe-plate, but in the
manner usual with steel-plates, by filling the lines
with ink, cleaning and iwlislung the surface of the
plate, and tlien laying the paper upon it and pa.ss-
ing both tlirough the press (Fig. 1445), when the
paper absorbs the ink from the lim^s of the plate.
The rose-engine work around the portrait, if print-
ed from by the surface-process directly as it was en-
graved, would give a black surface witii a fine tracery
of white lines ; but, to ad;ipt it to show its fine lines
colored on a white gi'ound, a counterpart impres-
sion in steel nuist be made, in whii'li tlie lines are
salient, not depressed, and this by transfers is made
so to ai>pear in the plate, that by printing the por-
trait and its border in a single op.'ration of surface-
printing, we have the portrait wliite-line work on a
dark ground, and the burder dark-line work on a
white ground.
Tlie author is indebted for this uniiiue .specimen
to G. ^V. (Vwil.-ar.
Sur'face-roU'er. {Calico-printing.) The en-
graved cylinder used in calico-printing.
Sur'fac-ing-ma-chine'. 1. {Wood-working.)
A machine for pl.ming timber. The piece is fed by
weighted corrugated feed-rolls to rotary cutters,
which smooth its surface ; bearing roUeis at eacli
end of the machine steady and equalize tlie motion
of the piece (Fig. G0S2).
Tbe belt of the driving-puliey is thrown in or out of action
by a tension -roller connected with a luind-Iever manipulated by
the operator. The table or platen may be raised or lowered by
two screws gearing with a cross-shaft operated by a band-
wheel.
The machine (Fig. 6083) is designed for Gnishing olT metallic
surtaces by grinding. It is provided with a wheel faced with
tanile. (See Tamte.)
Fig. 6082. ^^ Tlie upper part of the
wheel may lie permitted
to project very ^liglitly
above a central tran.i-
ver>i, opening in the
bid on which the work
1 u ed and pi-esented
the action of tlio
1 Tbe bed is raided
Surfacing-Machinf. ^="
or lowered by means of two worms whicli engage worm-wheels
at tbe upper ends of two screw standards entering circular
openings at either end of the compound pillar which form.s the
base of the machine.
Fig. 6083.
Emfry-Whtel Siirfaring-Markine.
Surf-boat. A peculiarly constructed boat for
landing or pushing ott' through the surf. See C.\TA-
M.'Ml.^X ; LiFF.-BOAT ; M.A.SS0(1L.\1I-B0.\T.
Stirge. {Nautical.) The swell on a windlass-
barrel upon wliich the cable or messenger surges or
slips back.
Surge-re-liev'er. A s]iring interposed between
an object sulijecti'il to suililen strain and a relatively
immovable object <u- one dilticult to start. Such are
jilaced on some pulley-blocks, to prevent their being
snatched away ; in iiarness, between the trace and
the wagon ; in cables, to take oH' suildenness of the
jerk upon tlie bitt, windlass, capstan, or cable-stop-
per. See patent 27,505, March 13, 1860. See also
Plate LXVn
MEPAM-ION HEAD OF COMMODORE PEKRY.
SPEriMEN OF SURFACE PRINTIXG.
See pp. 2458, 2459.
SURGE-SPRING.
2459
SURGICAL INSTRUMENTS.
Sur'gi-cal
Fig. G084. Draft - spuixft ; Spring - coup-
lino ; etc.
Surge-spring. See Surge-ue-
LiEVEi:; DiiAFT-brRiXG; Spring-
ClUl'LING.
Ap-pli'an-ces.
{^unjical.) Ap-
paratus — perhaps
rather as distinct
from instruments
— embracing band-
ages, splints, api)a-
ratus lor weak, de-
Ibrnied, luxated, or
fractured limbs;
shoulder and spinal braces
and supporters ; specific con-
trivances for extension and
counter-extension ; fordeflec-
tionsand local muscular and
vascular relaxation. See list
ol SrRGK'AL InsTKUME.NTS.
Sur'gi-cal In'stru-
meuts.
The word .wr^^on, or chinirgeon,
is derived from the Greek x^<-P aud
epyeti', signifjiug to work with the
hand, and plainly indicative of the
manipulations, topical treatment,
and even palmistry. The healing
art of the physician was early dis-
sociated from that of the operative
surgeon, as appears
iu the oath of Hip-
pocrates, who for-
bade the practice of
Surgical Appliances. lithotomy to the
physician. In a con- .
dition of things still more remote, the medicine-man was a priest,
as he is to-duy iu Egypt, India, China, and Japan, and among i
savage and half-civilized peoples. j
The surgeons of Egypt are the earliest of whom we have
record. The basso-rilievos of Thebes display instruments and
operations similar to those of the present. Venesection and
circumcision are among the earliest mentioned. The art of
embalming, as of healing, was practiced by the priest*, and the
physicians of note were deified both in Egypt aud in Greece. As-
clepiasin the former, or Esculapius, in the latter, were demi-gods,
the lattf-r being reputed to be tlie son of Apollo , and to have accom-
panied Melampus and Chiron as surgeons on a warlike expedi-
tion, about 1242 b. c-, fifty years before the fallofTroy. Machaon
and Podaliriua, two sons of Esculapius, were army surgeons with
the Greeks in the Troad. Danmcedes, 600 B c. , was taken
prisoner by the Persians, and became court physician in Persia,
reducing a dislocation of the ankle for Darius, and removing a
cancer for his queen Atosa. Ilerophilus and Erisistratus, of
Alexandria, made that school famous in the third century, B- c,
and are reputed to have dissected the human bod}'. The tour-
niquet, catheter, lithontriptor, and ecraseur were probably
used by them. Galen practiced in Itome in the second cen-
tury, A. D
Fig 6085 shows a number of surgical instruments discovered
by the Russian physician, Dr. .Savenko, in 1819, in the Via
Consularis, Pompeii. The instruments are in the Museum of
Portici They were discovered in a house supposed to have
belonged to a surgeon. They are, —
n 6, two probes {speciitum) respectively six and four and a
half inches long.
c, a cautery of iron, four inches long.
c/ e, two lancets {scalpellum) of copper, four and a half and
three inches long
/, a small copper amputating-knife, with a wavy edge. The
illustration (taken from Hevtie JMedicale, for 1821, Vol. III.
page 427) showsit out of proportion ; it is twoand a half inches
long, one inch broad, and has a thick back adapted to be struck
by a mallet,
g, a scalpel, with a probe point.
/i, an iron needle.
I, an elevator for raising depressed portions of the skull. ,
7,7 ^• /.different kinds of forceps ; 2 is a tenaculum forceps, with ,
a running ring.
7/1, hair tweezers. !
n, esophagus forceps. [
p, catheters {male and female).
V, uvula forceps.
r s, spKtuias. '
The library of the Surgeon -General's office, Washington, |
D. C. , has been formed since the close of the war, and now con- '
tains about 39,000 volumes, besides about 20,000 pamphlets. I
Fig. 6085.
!>urgical Inslruments found at Pompeii.
It is really the National Medical Library of the United States,
is catalogued and managed like the Congressional Library, and
is intended for the benefit of the entire profession of the country.
It is a very good practical working library, and is especially rich
in periodicals.
From the priests the profession of surgery seems to have
pas.=ed to the barbers, the term bnTber-sursiton being much
older than that of surgeon. The fourth Lateran council, in
993, forbade the " shedding of blood '' by the priests, and thus
continued in force the old distinction between medicine anri
surgery which was enforced by Hippocrates, and is yetjialously
maintained in European countries. Farther pnpal interference
by the.seventh Lateran council in 1131. and the Council of Tours
in 1163, disassociated the clergy from medicine, which then fell
to the apothecaries, as surgery had to the barbers, who were
also keepers of the baths. French and English charters and
municipal regulations show that the profession was gradually
assuming systematic proportions, court and army surgeons be-
coming of note, the chiruT^eon proper, who also studied medi-
cine, gradually edging away from the mere barber-surgeons^
who simply shampooed, bled, blistered, cupped, drew teeth,
and bound up the wounds of the victims of the frequent frays.
The chirurgeon proper wore a robe and cap, when, in 1572,
bluff King Harry granted the Royal College of Physicians of
London the power of licensing practitioners in the city of Lon-
don and within seven mile.'* thereof, — a right still extant.
Tho distinction between chinirgiens and perriif/in'ers was fnirly
drawn by enactment in France, ie7)ip. Louis XIV., and in Eng-
land in 1745, by act of Parliament, te77ip. George II
Sur'gi-cal In'stru-ments and Ap-pli'an-ces.
See under the following; heads : —
Abaptiston.
Abdominal supporter.
Acanthalus.
Accipter.
SURGICAL INSTRUMENTS.
2460
SURGICAL INSTRUMENTS.
Acoumeter.
Acoustic instruments.
Acupuucturator.
AcUi'.
Acutenaculum.
Alphousiu.
Ambe.
Amputu,tiDg:-knife.
Aiiiputating-saw,
Ana^stlietic refrigerator .
Aufe^tlietic-3. luiStruaitiDts for
applying
Anal dilator.
Anal speculum.
Anaplastic instrument.
Anchylosis-apparatus.
Ancycloniele.
Aneurism-needle.
Aneurism- tourniquet.
Aortic compressor.
Applicator
Arm, Artificial
Arterial compressor.
Artery -claw.
Artery- forceps.
Arteryotome.
Articulator.
Artificial arm.
Artiticial auricle.
Artificial ear.
Artificial eye.
Artificial foot.
Artificial gums.
Artiticial hand.
Artiticial leech.
Artificial leg.
Artificial limb.
Artificial nipple.
Artificial no.ie
Artificial palate.
Artificial pupil.
Artificial teeth.
Artificial tympanum.
Astigmatism-apparatus.
Atomizer.
Auricle. Artificial
Auriscalpum.
Auriscope
Auto laryngoscope.
Auto-ophthalmo-scope.
Autopsy-instrumeut.
Bandage
Barora aerometer.
Bath.
Bdelometer.
Bidet.
Bistoury.
Blooding-stick.
Blunt hook.
Body-fupporter.
Bone-chisel.
Bone-drill.
Bone-elevator.
Bone-forceps.
Bone-scraper.
Bone-stafil
Bougie
Breast-cup.
Breast pump.
Branchotome.
Bullet-extractor.
Bullet-forceps.
Bullet-probe.
Bullet-scoop.
Bullet-screw.
Burial-case.
Oalculi-forceps.
Calculi-instruments.
(Jane trumpet.
Cannula.
Canon .
Caponizing-tastrument.
Cardiometer.
Castrating-clamp.
Catamenial bandage.
Catamenial supporter.
Cataract-knife.
Cataract-needle.
Catarrhal syringe.
Catheter.
Cathoter-gage.
Cathefer-syringe.
Cathetometer.
Catling.
Cauterizing instrument.
Cautery.
Cau ting-iron.
Cephalotome.
Cephalotribe.
Ceratome
Chain -saw.
Chain-saw carrier.
Chiropodic instruments.
Choudrotome.
Cionotome.
Circular saw.
Cirsotome.
Claw. Obstetric
Clinical thermometer.
Cliseometer.
Club feet Apparatus for
Coaptator.
Coffin.
Compress.
Compressor.
Conductor.
Conges tor.
Conversation-tube.
Coreotome.
Cornet.
Corn -knife.
Corns. Instrument for remov-
ing
Corpse-preserver.
Cos to tome.
Couching-instrument
Counter-extension apparatus.
Cradlft
Crane-bill.
Craniotome.
Cranio tomy-forceps.
Creosote appliances.
Crotchet.
Crow's-bill.
Crutch.
Cucurbitula.
Cup.
Cupping-instruments.
Cupping-pump.
Curette.
Cutiseetor.
Cystitome.
Cystotome.
Decantation.
Decussorium.
Dental forceps.
Dental hammer.
Dental instruments.
Denti-scalpium.
Deodorizer.
Dermal instruments.
Dermopathic instrument.
Diacaustic.
Dilator.
Director.
Disinfecting-apparatufl.
Dislocation-ap paratus .
Dissecting-forceps.
Dissecting-knife.
Dock -holder.
Dossil,
Douche.
Drop ping- tube.
Ear. Artificial
Ear-cornet.
Ear instruments.
Ear of Dionysius.
Ear -speculum.
Ear-spoon.
Ear-syringe.
Ear- trumpet.
Frfiraseur.
Ectropium.
Electro-magnetic machine.
Electro-medical apparatus.
Electro-puncturing.
Elevator. Bone
Endoscope.
Endosmouieter.
Enema-syringe.
Euterotome.
Entropium.
Entropium-forcep.'i.
Esophagus-forceps.
Esthesiometer.
Eustachian-tube instrument.
Exercising-machine,
Exsecting-saw.
Exsectinn -apparatus.
Extension.
Extractf)r
Eye. Artificial
Eye-cup.
Eye-extirpator.
Eye -forceps.
Eye-instruments.
Eyelid-dilator.
Eye- pro tec tor.
Eye-speculum.
Eye-syriDg&
Fibula.
Firing iron.
Fissure- needle.
Fleam.
Fermentation -apparatus.
Foot. Artificial
Forceps.
Fourchette.
Fracture -apparatus.
Fracture-supporter.
(ialvauic moxa.
Garrot.
Goggle.
Gonorrhea-syringe.
Gorget.
Gums. Artificial
Hamulus.
Hand. Artificial
Hearing- trumpet.
Hcmadynamometer.
Hemorrhage-instrument.
Heuiorrhoidal syringe.
Hernia-instruments.
Hernia-supporter.
Hey's saw.
Hypodermic syringe.
Hysterometer.
Hysterotome.
Inhaler.
Injection -syringe.
Insufflator.
Invaginatorium.
Iriaskistrum,
I ridec tomy-i ns trument.
Iridioscope.
I rri tation - i us tr umen t.
J aw- lever.
Keratome.
Key. Dental
Kioto me.
Knife,
Labidometer.
Lachrymal- duct dilator.
Lactose ope.
Lancet.
Langate.
Laparotome.
Laryngeal ecraseur.
Laryngosi-ope.
Leech. Artificial
Leg Artificial
Levator.
Lever. Obstetric
Ligating- forceps.
Ligature-carrier.
Ligatnre-tyer.
Limbs. Artificial
Lint.
Lithoclast.
Litholabe.
Lit holy te
Lithontriptor.
Lithotome.
Lithotomy cach^.
Lithotomy-forceps.
Lithotomy-gorget.
Lithotomy -searcher.
Lithotomy -sound.
Lithotritor.
Locking- forceps.
Mallet. Dental
Manikin.
Manumeter.
Masticator.
-Meatu scope.
Meatus knife.
MedicJitor.
Medicinal cup.
Menstrual supporter.
Metacarpal saw.
Metrenchytes.
Metrometer.
Metroscope.
Metrotome.
Microcaustic.
Milking-shield.
Mortar.
Mouth-speculum.
Moxa.
Nasal irrigator.
Nasal speculum.
Needle,
Needle- forceps,
Needle-holder and tools.
Needle. Surgical
Nerve-needle.
Neurotome.
Nipple. Artificial
Nipple-shield
Nose. Artificial
Nursery-bottle.
Obdurator.
Obstetrical forceps.
Obstetric instruments.
Odontagra.
Ointment-syringe.
Operating-table.
Opsiometer.
Ophthalmometer.
p h tha I m osco pe .
Ophthalmostate.
Opsiometer.
Organic vibrator.
Orthopoedic apparatus.
Osmometer.
Otophone.
Otoscope.
Pad for trusses.
Pedometer.
Palate. Artificial
Parallel-knife.
Paring-knife.
Paring-scissors.
Patella-apparatus.
Pelvimeter.
Penis-syringe.
Percussor.
Perforator. Obs te t ric
Periodoscope.
Periosteum-elevator.
Phacocys tec tome.
Pharyngotome.
Pile-supporter.
Pill-machine.
Pill-tile.
Placenta-forceps.
Placenta-book.
Plaster-machine.
Plaster-spatula.
Plate for artificial teeth.
Pleximeter.
Pneumatometer.
Polypus-forceps.
Porte-aiguille.
Porte-caustic.
Porte-cordon.
Porte-meche.
Post-mortem case.
Probang.
Probe.
Probe-syringe.
Prolapsus-instrument.
Pterygium.
Pulmometer,
Pulsometer.
Pupil. Artificial
Racbitome.
RiLspatory.
Remora.
Respirator.
Retractor.
Retro version-instrument
Rhinoplastic knife.
Rhinoplastic pin.
Rhinoscope.
Rostrum.
Roweling-needle.
Roweling-scissors.
Rvipturing-forceps.
Saliva-pump.
Scalpel.
Scalper.
Scalprum.
Scarificator.
Scissors.
Scissors. Canalicula
Scissors. Conjunctiva
Scissors . Dissecting
Scissors. Harelip
Scissors. Iridectomy
Sci)»sors. Pterygium
Scissors. Roweling
Scissors. Strabismus
Scoliosis- brace.
SrKGICAL XEEDLE.
24(31
SURVEYOR'S-CROSS.
Searcher.
Searinz-iron.
Segment-saw.
Serre-fin.
Serre-noeud.
Seton.
Se ton-needle.
Shoulder-brace.
Solen.
Soai&er.
Soand.
Spatula.
Specnlom.
S |>ec ul om-forceps .
Spermatorrhoea. Apparatus for
P permaiorrhcea-syringe.
SphvgmoCTaph.
S pb Tgmometer.
S phygmoeco pe.
Spinal-distortion app&ratos.
Spinal supporter.
Spirometer.
Splint.
Sponge-tent
SpooD. Medicinal
Spring for artificial teeth.
Staff.
Staph vloraphic instruments.
S team-aicomzer .
Stethometer.
Stethoscope.
Stilette.
S lomach-pnm p.
Stouiatoscope
S tnbismas- forceps.
St rabismus-sc iss^rs -
Stricture-cutter.
S trie t ure-dilator.
Stylet.
Subcutaneous saw.
Supporter.
Surgical needle.
Suspension-bandage.
Suture-conductor.
Suture-instrument.
Synoeteotome.
Syringe.
Syringe-case.
Smngotomc-
l^ble. Operating
Talipes-apparatus.
Tampon.
Tape-worm apparatus.
Tenaculum.
Tenotome.
Tent.
Testes-supporter.
Tonsilotome.
Tooth. Artificial
Tooth. Saw
Torcular.
Tourniquet.
Trachea-forcepa.
Tracheotome.
Trac heotomy-tube.
Tractor- Obstetric
Trans fusion -syringe-
Trepan-saw.
Trephine.
Trilable.
Trocar.
Truss.
TumkeT.
Tympanometer
Tympanum. Artificial
Universal syringe.
t'ranicoplastic instruments.
Urethra-cutter.
Urethra syringe.
Urethratome.
Urinometer.
Utereotome
Uterine dilator.
Uterine douche.
Uterine elevator.
Uterine redresser.
Uterine scarificator.
Uterine speculum.
Uterine-support director.
Uterine supporter.
Uvula-forceps.
Vaccinator.
Vacunra-apparatus.
Tji^nal speculum.
Vaginal supporter.
Va^nnal syringe.
Vaporarium-
Vapor-inhaler
Varicose stockings.
Veens.
Ventouse.
Xvster.
^60S&
Ta ii pes-i ns trumeo ts .
Sur'gi-cal Knife. See vmderthefoUowino: heads:—
Amputating-kmie. Lancet-
Arteryotome. Meatus-knife.
Bistoury. Metrotome.
Cataract-knife- Parallel knife-
Catling. Pbaryngotome.
Costoiome. Scai pel .
Dissecting- knife. Tenotome.
Double knife. Tonsilotome.
Hysterotome. Urethraiome.
Keratoma Utereotome.
Snr'gi-cal Nee'dle. One usetl for sewing up
woundb and cuts. They are of various shajws and
sizes.
A surreal needle, of the osnal bent form,
was disinterred at Pompeii in 1S19, in com-
pany wich a variety of surgical instruments :
lancets, catheters, probes, forceps (Fig. 6IJ&5).
Sar'mark. {Shiphnildinfj.) a. A
mark <ira\vn on the timbei*s at the
iiiterse»nion of the moKiiiig-edge with
the rihlxind-line; the stations of the
ribbands and harpings being marked
on the timbers.
h. A cleat temporarily placed on
the outside of a rib, to give a hold to
the ribband by which, through the
Sitrgical Needles, shores, it is supported on the slip-
way.
Sur-vey'. a. An examination of a tract as to
extent, contour, divisions, etc.
b. A plan showing the saiil features, or fiome of them.
A trigoncmetrieal survey i^ one made by triangulations, as
the coast survey of the United States, the ordnance survey of
England.
In a geodftieal stirvey, the curvature of the earth is taken
into account.
Ma^tinie or nautical surveying concerns the coast, and gives
bearing of prominent objects, positions of shoals, depths of wa-
ter, etc.
Ptane surveying does not take the curvature of the earth into
account, as does gfodetie.
Toposraphical survey deals with the poeitious of planes on
the surfece of the earth.
Sur-vey'mg-in'stra-ineiits. See, —
Astrolabe. Odometer.
Circumferentor. Optical square.
C<Hnpass-prismatic. Plane-table
Geometric square. Sector.
Demi-circle. Sextant.
Jacob-staff Station -pointer.
Level S urvey i ng-cross.
Leveling-staffi Surveyor's chain.
Object-staff Theodolite.
Sur-vey 'or's-chain. This chain, called Giniiers,
after the name of the person who adapted it, is 4
rods or 66 feet long, made of Nos. 6 to 9 wire, and
has 100 links. 10 of these s^juare chains are etpial
to an acre. 66x66x10 = 43,560 feet = lacre; or,
counting by links, 100x100x10 = 100,000 S4|uare
links = 1 acre.
The chain is di>-ided Fig.60S7.
every 10 links by notched
brass marks, so that the i
fractions may be readily
distinguished.
Chains 100 feet lon^
divided into 1-foot links,
are also used by civil en- Surveifor's- Chain.
gineers.
Other apparatus is used where extreme accuracy
is re<]uired.
The decempeda, or 10-foot pole, was the standard
land-measure of Rome.
The ba-*ie line for the trigonometrical survey of Great Britain
was laid down by General Roy on Hounslow Heath, and is 5.2
miles long, nearly. It was measured at first with pine rods;
but as these were found to be affected by the hvCTometrical
changes of the atmosphere, it was again measured with gla.ss
tube« 20 feet in length, furnished with a peculiar apparatus for
making the contacts. In the subsequent measurement of the
same line for the Ordnance Survey, two steel chains of 1<X* feet
in length, and made by Ramsden, were employed. One of these
was kept as a measuring-chain ; the other was kept for the pur-
pose of comparing the measuring-chain with it b«"fore and after
the operation. In the act of measuring, the chain was laid in
a trough supported on trestles, and was stretched with a weight
of .56 pounds^ The same apparatus was employed in measuring
five other bases in different parts of the country, for the pur-
pose of verifying the accuracy of the work.
For the measurement of the Lough Foyle ba.«e in the survey
of Ireland, nearly S miles in length, Colonel Colby employed a
compensating apparatus formed of bars of different metals, so
arranged that the distance between the two points viewed by
compensation microscopes remains constant under all changes
of temperature- For account of measurements of degrees of
latitude, see Oik)MEter
"The method of iriangulation in a great survey, by means of
quadrilaterals, is purely .\merican in its origin, having been
first introduced by the late Professor Bache." — Prof. Peirce,
Sur-vey 'or's-com 'pass. The m easu ring-con j-
pass \v;is invented by Jost Bing of Hesse, in 1602.
See CiKcrMFERENT'iR ; Tueodolite.
Sur-vey'or's-cross, An instrument employed
for establishing peri>endicular lines in surveying. It
has four sights fixed at right angles upon a brass
SuTTeyiTig- Ooas.
SUSPENDER.
2462
SUSrENSION-BRIDGE.
cross, which can be screwed to a tripod or single
statf. Tlie instrument is adjusted so that one pair
of sights coincitle with a given or base line, when a
line perpendicular to tiie former can be easily ob-
served, traced, or set out by viewing through the
othi-r pnir of sights («, Fig. 6088).
A cylintlrical or octagonnl box of brass, called the optical
Sf/unrf, b (i, is used for the same purpose as the instrument
witb four sights on the braj*s cross. The box has four vertical
fitits answering to the four sights just mentioned, and inside
the box are tlie two principal ghisses of the sextant, the index
and horizon glasses, placed at an angle of 45° (r, Fig H0S8), so
that, when viewing an object by direct vision, any other form-
ing a right angle with it at the place of tlie observer will be
seen by reflection to coincide with the object viewed. Placing
the instrument in such a position as to look along any given
line, the surveyor is enabled to direct the planting of a station-
staff at right angles thereto. Some of thi-sc instruments are
made small enough to be carried in the pocket.
Sus-pend'er. A strap or ])air of crossed stra]is
over the shoulders to hold up the trousers. They
usiuiUy have bifurcated ends in front and single ends