Knight's Mechanical Encyclopedia, P., Pyro-pho-tog′ra-phy.

Home Collections/Texts Perseus Catalog Research Grants Open Source About Help

Hide browse bar Your current position in the text is marked in blue. Click anywhere in the line to jump to another position:

This text is part of:

19th-Century American

View text chunked by:

chapter : entry
entry

Table of Contents:

Pach-om′e-ter.

Pack′ag-ing-ma-chine′.

Pack′et-note.

Pack′ing-awl.

Pack′ing-bolt.

Pack′ing-box.

Pack′ing-press.

Pack′ing-ring.

Pack′ing-stick.

Pack-sad′dle.

Pad-crimp press.

Pad′ding-ma-chine′.

Pad′dle-box boat.

Pad′dle-hole.

Pad′dle-pro-pel′ler.

Pad′dle-wheel.

Pad-trace Bear′er.

Pad-u-a-soy′.

Pae-dom′e-ter.

Pag′ing-ma-chine′.

Pail-ma-chine′.

Paint-burn′er.

Pair-horse Har′ness.

Paix ′han gun.

Pal′ate, Artifi′cial.

Pal′ette-knife.

Pal′ier-glis′sant.

Pal′imp-sest.

Pal-la′di-um-izing.

Pallam-poor′.

Pal′let-mold′ing.

Pal-li-asse′.

Palm-leaf loom.

Pan-a-ma′ hat.

Pan-de′an pipes.

Panei-cono-graph.

Pan′el-plane.

Pan′el-rais′er.

Pan-ic′o-graph.

Pan-nus-co′ri-um.

Pan-o-ram′ic Cam′e-ra.

Panste-re-o-ra′ma.

Pan-tel′e-graph.

Pan′to-chro-nom′e-ter.

Pan′to-graph.

Pan-tom′e-ter.

Pa′per-bag ma-chine′.

Pa′per-box ma-chine′.

Pa′per-clamp.

Pa′per cloth.

Pa′per Col′lar.

Pa′per-col′or-ing ma-chine′.

Pa′per-cut′ter.

Pa′per-cut′ting ma-chine′.

Pa′per-en-am′el-ing ma-chine′.

Pa′per-feed′er.

Pa′per floor-cloth.

Pa′per-fold′er.

Pa′per-fold′ing ma-chine′.

Pa′per-hang′ing.

Pa′per hot-press.

Pa′per-knife.

Pa′per-mak′ing ma-chine′.

Pa′per-mold′ing ma-chine′.

Pa′per-mus′lin.

Pa′per-per′fo-rating ma-chine′.

Pa′per-pol′ish-ing ma-chine′.

Pa′per-punch.

Pa′per-rul′ing ma-chine′.

Pa′per-split′ting.

Pa′per-stock Bleach′er.

Pa′per-stock Wash′er.

Pa′per-tube ma-chine′.

Pa′per-twine.

Pa′per Wa′ter-proof′ing Machine′.

Pa′per-weight.

Pa′pier-mache′.

Par-a-bol′ic Il-lu′mi-na′tor.

Par-a-bol′ic Reflect′or.

Par′a-cen-te′ri-um.

Par-a-chute′.

Par-a-chute′--light.

Par-a-chute′--light ball.

Par′a-gran′di-ne.

Par-a-grele′.

Par′al-lel bar.

Par′al-lel file.

Par′al-lel knife.

Par′al-lel lathe.

Par′al-lel Mo′tion.

Par′al-lel Rul′er.

Par′al-lel vise.

Para-ton-nerre.

Par′cel-ing-ma-chine′.

Parch′ment-pa′per.

Par′ing-ma-chine′.

Par′ing-plow.

Paring-scis′sors.

Par-is′ian gold-col′ored Al′loy.

Par-is′ian white-metal.

Pa-risth′mi-o-tome.

Par′lia-ment-heel.

Par′lor-skate.

Pa′ros-mar′ble.

Par′point-work.

Par′ral-rope.

Par′rott-gun.

Part′ing-sand.

Pas-de-sou′ris.

Passe-par-tout′.

Pass′ing-place.

Pasteboard-cut ′ter.

Paste-mak′er.

Pat ′a-mome-ter.

Pa-tel′la-ap′Pa-ra′tus.

Pat ′ent Leath ′er.

Pat ′e-re′ro.

Pa′ter-nos′ter — pump.

Pa′ter-nos′ter-wheel.

Pat ′tern-box.

Pat ′tern-cyl′in-der.

Pat ′tern-makers' Ap-pli′an-ces.

Pat ′tern-wheel.

Pat ′tin-son's pots.

Pa-vil′lon-chi-nois′.

Pav′ing-bee′tle.

Pav′ing-ma-chine′.

Pav′ing-roll′er.

Pav′ing-tile.

Peach-par′er.

Peach-ston′er.

Pea-drop′per.

Peak-hal′yards.

Pea′nut-dig′ger.

Pea′nut-pick′er.

Pearl , Arti-fi′cial.

Pearl-barley ma-chine′.

Pearl-but′ton.

Pearl ′ing-mill.

Pearl-pow′der.

Pea-shell′er.

Peat-burn′ing Furnace.

Peat-cut ′ter.

Peat-ma-chine′.

Peb′ble-pav′ing.

Pedal-or′gan.

Ped′es-tal-cov′er.

Ped′i-ment-ba-rom′e-ter.

Pe-dom′e-ter.

Peel ′ing-i′ron.

Peg-cut ′ter.

Peg′ging-awl.

Peg′ging-ma-chine′.

Peg′ging-ram′mer.

Pei-ram′e-ter.

Pel′le-tan-jet.

Pel-vim′e-ter.

Pely-com′e-ter.

Pen′cil-com′pass.

Pen′cil-sharpen-er.

Pen′dant-wind′ing watch.

Pendu-lous-cylin-der steam-en′gine.

Pen′du-lum-hausse.

Pen′du-lum-lev′el.

Pen′du-lum-pump.

Pen′du-lum-wheel.

Pen′du-lum-wire.

Pen-i-cil′lus.

Pe′nis-syringe.

Pen′nis-tone.

Pen′ta-graph.

Per-am′bu-lator.

Per-ca-line′.

Per′co-la-tor.

Per-cus′sion-cap.

Per-cus′sion-cap Filling-ma-chine.

Per-cus′sion-cap Hold′--er.

Per-cus′sion-cap Trim′ming-ma-chine.

Per-cus′sion-fuse.

Per-cus′sion-grind′er.

Per-cus′sion-lock.

Per-cus′sion-pow′der.

Per-cus′sion-sieve.

Per-cus′sionstop.

Per-cus′sionta′ble.

Per′fect-ing.

Per′fect-ing-press.

Per′fo-rat′ed file.

Per′fo-rated saw.

Per′fo-rat′ing-ma-chine′.

Per′fo-rator, Ob-stet′ric.

Per′i-a′gua.

Pe-ri-od′o-scope.

Peri-os′te-um-el′e-va-tor.

Per′i-scop′ic lens.

Per′ma-nent way.

Per-mu-ta′tion-lock.

Per′pen-dic′u-lar lift.

Per-pet′u-al Mo′tion.

Per-pet′u-al screw.

Per-ro-tine′.

Per′sian Carpet.

Per′sian drill.

Per′sian wheel.

Per-spec′tive-glass.

Per-spec′tive-instru-ment.

Per-spec′to-graph.

Pe-tro′le-um.

Pe-tro′le-um-burn′er.

Pe-tro′le-um-car.

Pe-trole-um-fil′ter.

Pe-tro′le-um-fur′nace.

Pe-tro′le-um-lamp.

Pe-tro′le-um-still.

Pe-tro′le-um-stove.

Pe-tro′le-umtank.

Pe-tro′le-umtest′er.

Pet′ti-coat-pipe.

Pew′ter-er's Sol′der.

Pew′ter-er's Tem′per.

Pha′co-cys′tec-tome.

Phan-tasma-go′ri-a.

Phan′ta-scope.

Pha-ryn′go-tome.

Phena-kis′to-scope.

Pho-nau′to-graph.

Pho′no-graph.

Pho′no-scope.

Phos′phor bronze.

Phos-phor′o-scope.

Phos′pho-rus-paste.

Pho′to-e-lec′tric lamp.

Pho′to-e-lec′tro-type.

Pho′to-en-grav′ing.

Pho′to-gal-van′o-graph.

Pho′to-gel′a-tine Pro′cess.

Pho-to-gen′ic Draw′ing.

Pho-to-glyph′ic En-grav′ing.

Pho-to-glyp′tic En-grav′ing.

Pho′to-graph-e-namel.

Pho-to-graph′ic Cam′e-ra.

Pho-to-graph′ic Cam′e-ra-stand.

Pho-to-graph′ic chair.

Pho-to-graph′ic Cut′ter.

Pho-to-graph′ic head-rest.

Pho-to-graph′ic mi-crom′e-ter.

Pho-to-graph′ic Print′ing.

Pho-togra-phom′e-ter.

Pho-tog′ra-phy

Photo-he′li-o-graph.

Photo-hy-al′o-type.

Pho′to-in-tagl′io En-graving.

Photo-li-thogra-phy.

Pho′to-me-chan′i-cal Print′ing.

Pho′to-me-tallo-graph.

Pho-tom′e-ter.

Photo-mi-cog′ra-phy.

Pho′to-pro′cess-es.

Pho′to-re-lief′ En-grav′ing.

Pho′to-scope.

Pho′to-sculp′ture.

Pho′to-vit′ro-type.

Photo-zin-cog′ra-phy.

Phthon-gom′e-ter.

Pi-a′no-for′te.

Pi-a′no-for′te Ac′tion.

Pi-a′no-for′te Ham ′mer.

Pi-a′no-graph.

Pi-a′no-jack.

Pi-a′no-lock.

Pi-a′no-move′ment.

Pi-a′no-stool.

Pio ′co-lo-flute.

Pick′er-mo′tion.

Pick′er-staff.

Pick′et-clamp.

Pick′et-point′er.

Pick-ham′mer.

Pick′ing cloth.

Pick′ing-peg.

Pick′ing-stick.

Pic′ture-nail.

Pierc′ing-file.

Pierc′ing-saw.

Pierre per-due′.

Pi-e′tra Du′ra.

Pie-zom′e-ter.

Pig′eon, Me-chan′i-cal.

Pig-i′ron Break′er.

Pig′mentprint′ing.

Pile-car′pet.

Piled-fab′ric loom.

Pile-draw′er.

Pile-driv′er.

Pile-fab′ric.

Pile-sup-port′er.

Pile-with-draw′ing ma-chine′.

Pil′lar-block.

Pil′lar-com′pass.

Pil′lar-file.

Pill-ma-chine′.

Pil′low-block.

Pil′low-lace.

Pi-lon′--mill.

Pi′lot-cloth.

Pi′lot-en′gine.

Pinch′ing-bar.

Pinch′ing-nut.

Pinch′ing-pin.

Pinch′ing-tongs.

Pine-leaf Fab′ric.

Pine-wood still.

Pin′ion-file.

Pin′ion-gage.

Pin′ion-wire.

Pink′ing–i′ron.

Pin′ning–in.

Pin–pa′per-ing ma-chine′.

Pipe–clear′er.

Pipe–coup′ling.

Pipe–cut′ter.

Pipe-driv′er.

Pipe-mold′ing.

Pipe-prov′er.

Pipe-slotting punch.

Pipe-sock′et-ing ma-chine′.

Pipe-thread′ing ma-chine′.

Pip′ing-i′ron.

Pi-que′--work.

Pi-ram′e-ter.

Pi-se — work.

Pis′tol-car′bine.

Pis′tol-pipe.

Pis′tol-rout′er.

Pis′ton-bel′lows.

Pis′ton Blow′ing-ma-chine′.

Pis′ton-head.

Pis′ton-head valve.

Pis′ton-pack′ing.

Pis′ton–rod.

Pis′ton–rod Pack′ing.

Pis′ton–spring.

Pis′ton–valve.

Pitch–back wheel.

Pitch–cir′cle.

Pitched Fas-cine′.

Pitch′ing–piece.

Pitch′ing–tool.

Pitch–wheels.

Pit′man–box.

Pit′man–coup′ling.

Pit′man–head.

Pi-tot's′ tube.

Piv′ot-bridge.

Piv′ot-broach.

Piv′ot-drill.

Piv′ot-gear′ing.

Piv′ot-lathe.

Piv′ot-tooth.

Piv′ot-tran′som.

Pla-cen′ta-for′ceps.

Pla-cen′ta-hook.

Plain-com′pass.

Plain-mold′ing.

Plait′ed rope.

Plait′ing-at-tach′ment for Sew′ing-ma-chines′.

Plan-chette′.

Plane-ash′lar.

Plan′er-cen′ters.

Plane-sur′face.

Plane-ta′ble.

Plan-et-a′ri-um.

Plan′et-gear.

Plan′et-wheel.

Pla-nim′e-ter.

Plan′ing-ma-chine′.

Plan′ish-ing.

Plan′ish-ing-ham′mer.

Plan′ish-ing-roll′ers.

Plan′ish-ing-stake.

Plan′i-sphere.

Plank ′ing-clamp.

Plank ′ing-ma-chine′.

Plank ′ing-screw.

Plank-re-vet′ment.

Pla′no-con′cave lens.

Pla′no-con′vex lens.

Pla-nom′e-ter.

Plan-ta′tion-mill.

Plaq′uage-style.

Plas′ter-cast.

Plas′ter-ers' tools and work.

Plas′ter-ing-ma-chine′.

Plas′ter-mill.

Plas′ter-spat′u-la.

Plate-bend ′ing ma-chine′.

Plate-en-grav′ing.

Plate-hold′er.

Plate-i′ron Gird′er.

Plate-leath′er.

Plate-pa′per.

Plate-plan′ing ma-chine′.

Plate-pow′der.

Plate-print′ing ma-chine′.

Plate-rail′way.

Plate-roll′er.

Plate-warm′er.

Plat′form-board.

Plat′form-bridge.

Plat′form-car.

Plat′form-car′riage.

Plat′form-crane.

Plat′form-scale.

Plat′i-niz-ing.

Plat′i-num-steel.

Pla-tom′e-ter.

Plat′ ten -ing glass.

Plensh′ing-nail.

Plex-im′e-ter.

Plot′ting-scale.

Plow-clean′er.

Plug-cen′ter bit.

Plug′ging-for′ceps.

Plug-ma-chine′.

Plumb ′er-block.

Plumber's force-pump.

Plumb ′er's Sol′der.

Plumb ′ing and sheet-met′al work and tools.

Plumb-lev′el.

Plum ′mer-block.

Plum ′met-lev′el.

Plun′ger-buck′et.

Plun′ger-pole.

Plun′ger-pump.

Plun′ging-bat′ter-y.

Plun′ging-fire.

Plush-cop′per.

Pluvi-am′e-ter.

Pneu-mat′ic Bat′ter-y.

Pneu-mat′ic Cais′son.

Pneu-mat′ic car.

Pneu-mat′ic dis-patch′--tube.

Pneu-mat′ic drill.

Pneu-mat′ic El′e-va′tor.

Pneu-mat′ic Ham ′mer.

Pneu-mat′ic hoist.

Pneu-mat′ic Le′ver.

Pneu-mat′ic Par′a-dox.

Pneu-mat′ic pile.

Pneu-mat′ic pump.

Pneu-mat′ic Rail′way.

Pneu-mat′ic spring.

Pneu-mat′ic Tel′e-graph.

Pneu-mat′ic trough.

Pneu-mat′ic tube.

Pneu-mat′ic tube-valve.

Pneu-mat′ic valve.

Pneuma-tom′e-ter; Pneumo-nom′e-ter .

Pock′et-a-larm′.

Pock′et-book.

Pock′et-knife.

Point′ed arch.

Point′ing-ma-chine′.

Point′ing-rods.

Point′ing-wire.

Point-pa′per.

Po′lar Cir′cle.

Po′lar clock.

Po′lar Di′al.

Po-lar′i-scope.

Polar-is-tro-bom′e-ter.

Pole-car′riage.

Pole-futch′el.

Po-lem′o-scope.

Pole-pro-pel′ler.

Pol′ished brick.

Pol′ish-ing-block.

Pol′ish-ing-cask.

Pol′ish-ing-file.

Pol′ish-ing glass.

Pol′ish-ing-ham′mer.

Pol′ish-ing-i′ron.

Pol′ish-ing-ma-chine′.

Pol′ish-ing-ma-te′ri-als.

Pol′ish-ing-mill.

Pol′ish-ing Nee′dles.

Pol′ish-ing-pow′der.

Pol′ish-ing-slate.

Pol′ish-ing-snake.

Pol′ish-ing-tin.

Pol′ish-ing-wheel.

Pol′y-chrome.

Pol-ym′e-ter.

Poly-op′tron.

Poly-pan′to-graph.

Pol′y-pus-for′ceps.

Poly-zo′nal lens.

Pon′til; Pon′ty ; Pon′tee .

Pon-ton′--bridge.

Po′ny-chaise.

Po′ny-en′gine.

Poop-lan′tern.

Pop′pet-head.

Por′ce-lain-cem′ent.

Por′ce-lain-gild′ing.

Por′ce-lain-mill.

Por′ce-lain-ov′en.

Por′ce-lain-pa′per.

Por′ce-lain-pic′ture.

Por′ce-lain-print′ing.

Porch-post Sup-port′.

Porphy-ri-za′tion.

Port′a-ble boat.

Port′a-ble Boil′er and Fur′nace.

Port′a-ble Der′rick.

Port′a-ble fence.

Port′a-ble Fur′nace.

Port′a-ble press.

Port′a-ble pump.

Port′a-ble Rail′way.

Port′a-ble steam-en′gine.

Port′a-ble stove.

Port-cul′lis.

Porte-ai-guille′.

Porte-bou-gie′.

Porte-caus-tique.

Porte-cor′don.

Porte-cray′on.

Porte-mon-naie′.

Porte-pi-erre′.

Porte-pol′ish-er.

Port-fire Clip′per.

Port-fol′io-stand.

Port-hole Clos′er.

Port′land Cement.

Port-lan′yard.

Port-man′teau.

Port mouth-bit.

Port-pen′dant.

Port-rig′gle.

Port-tack′le.

Pos′ing-appa-ra′tus.

Po-si′tion-mi-crom′--e-ter.

Pos′i-tive eye-piece.

Pos′i-tive Mo′tion.

Pos′i-tive-mo′tion loom.

Post′age-stamp.

Post and stall.

Post-hole Bor′er.

Post-hole Dig′ger.

Post-mor′tem case.

Post-of′fice box. 1 .

Post-pull′er.

Post-tab′u-la.

Po′tance-file.

Po-tas′si-um.

Po-ta′to-as-sort′er.

Po-ta′to-bug Clean′er.

Po-ta′to-dig′ger.

Po-ta′to-hook.

Po-ta′to-mash′er.

Po-ta′to-plant′er.

Po-ta′to-scoop.

Po-ta′to-sepa-ra′tor.

Po-ta′to-wash′er.

Potch′er-en′gine.

Poti-cho-ma′ni-a.

Pot′ter's lathe.

Pot′ter's wheel.

Pot′ter-y and clay.

Pot′ter-y-gage.

Pot′ter-y-kiln.

Pot′ter-y-mold′ing.

Pot′ter-y-paint′ing.

Pot′ter-y-print′ing.

Pot′ter-y-tis′sue.

Pot′ting-cask.

Pou-de-soy; Pad′e-soy ; Pod′de-soy .

Poul′tice-boot.

Poul′try-feed′er.

Pounce-pa′per.

Pouncing-ma-chine′.

Pounding-ma-chine′.

Pow′der-blow′er.

Powder-ing-mill.

Pow′der-mix′er.

Pow′der-prover.

Pow′er-ham′mer.

Poz′zu-o-la′na.

Praying-ma-chine′.

Pre-pon′der-ance.

Preser-va′tion of food.

Pre-serv′a-to-ry.

Pre-serve′--jar.

Pre-serv′ing wood.

Presse-ar-ter′.

Press′er-fly′er.

Press′er-foot.

Presse-u-rethre′.

Press′ing-bag.

Press′ing-board.

Press′ing-plate.

Press′ing-roll′er.

Press-print′ing.

Press′ure-blow′er.

Press′ure-en′gine.

Pressure-fil′ter.

Press′ure-forg′ing.

Press′ure-frame.

Press′ure-gage.

Press-wheel Roll′er.

Prick′ing-wheel.

Prime-con-duct′or.

Prim ′ing-horn.

Prim ′ing-powder.

Prim ′ing-tube.

Prim ′ing-valve.

Prim ′ing-wire.

Prince Ru ′pert's Met′al.

Prince 's Met′al.

Prin′ci-pal Raft′er.

Print′ed Car′pet.

Print′er's Flow′er.

Print′er's gage.

Print′er's Roll′er.

Print′er's Var′nish.

Print-hold′er.

Print′ing-bod′y.

Print′ing for the blind.

Print′ing-frame.

Print′ing-ink.

Print′ing-ma-chine′.

Print′ing-pa′per.

Print′ing-press.

Print′ing-tel′e-graph.

Print′ing-type.

Print′ing-wheel.

Print′ing yarn.

Pris-cil′las.

Pris-mat′ic Com′pass.

Prism-mi-crom′e-ter.

Prism-sphe-rom′e-ter.

Proche-ame-ter.

Pro′file-cut′ter.

Pro′file-pa′per.

Pro′fil-ing-ma-chine′.

Pro-jec′tile.

Pro-jec′tion.

Pro-lap′sus-in′stru-ments.

Pro-me′the-an.

Prop′a-gating-box.

Prop′a-gating-glass.

Pro-pel′ler-en′gine.

Pro-pel′ler-pump.

Pro-pel′ler-wheel.

Pro-por′tion-al Com′pass-es.

Pro-por′tion-al or Prim′i-tive Ra′--di-i .

Prop′y-lae′um.

Pros′o-pom′e-ter.

Pro′te-an-stone.

Pro-tec′tive Pa′per.

Pro-tract′ing-bev′el.

Pro-tract′or.

Prov′ing-hutt.

Prov′ing-ma-chine′.

Prov′ing-press.

Prov′ing-pump.

Pro-vis′ion-car.

Prun′ing-chis′el.

Prun′ing-hook.

Prun′ing-knife.

Prun′ing-saw.

Prun′ing-shears.

Prun′ing-tools.

Pseudi-sod′o-mon.

Pseu′do-dipter-al.

Pseu′do-pe-rip′ter-al.

Pseu′do-scope.

Psy-chrom′e-ter.

Pter-yg′i-um.

Pud′ding-stone.

Pud′dled steel.

Pud′dle-rolls.

Pud′dling-fur′nace.

Pud′dling-ma-chine′.

Puff′er-pipe.

Pul′ley-block.

Pul′ley-check.

Pul′ley-clutch.

Pul′ley-drum.

Pul′ley-mor′tised.

Pul′ley-sheave.

Pul′ley-stand.

Pul′ley Sus-pen′--sion-hook.

Pul′ley-wheel.

Pull′ing-jack.

Pull′man-car.

Pulp-boil′er.

Pulp-di-gest′er.

Pulp-dress′er.

Pulp-grind′er.

Pulp′ing-ma-chine′.

Pulp-ma-chine′.

Pulp-strain′er.

Pulp-wash′er.

Pul-som′e-ter; pul-sim′e-ter .

Pul′ver-izer.

Pul′ver-izing.

Pum′ice-stone.

Pump′ing-en′gine.

Pump-ket′tle.

Pump-pis′ton.

Pump-scrap′er.

Punch′ing and Shear′ing ma-chine′.

Punch′ing-bear.

Punch′ing buhl-work.

Punch′ing-ma-chine′.

Punch-pli′ers.

Pu′pil, Arti-fi′cial.

Pup′pet-head.

Pup′pet-valve.

Pur′chase-block.

Purg′ing-cock.

Pur′lin-post.

Push′ing-jack.

Put′tock-shrouds.

Put′ty-knife.

Put′ty-pow′der.

Puz′zle-lock.

Puzzo-la′no; Puozzo-la′no .

Pyc′no-style.

Pyr-heli-om′e-ter.

Py-roph′o-rus.

Pyro-pho-tog′ra-phy.

Pyr′o-ster′e-o-type.

Pyro-tech′nics.

Pyro-tech′nic Bal-loon′.

Py-rox′--line.

view as XML

Pyro-pho-tog′ra-phy.

A term including those processes in the photographic art in which the heat of a furnace is used to fix the picture. Enamel photography.

The picture copied must be on some transparent substance, or, if on paper, must be made transparent by the application of oil. The glass plate is covered with a coating of a certain gummy compound, which becomes hard under the action of light. The impression, when taken, is brought out by the application of a flux, and by heating the plate to a white heat is made permanent.

1877.

Tufts University provided support for entering this text.

view as XML

This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 United States License.

An XML version of this text is available for download, with the additional restriction that you offer Perseus any modifications you make. Perseus provides credit for all accepted changes, storing new additions in a versioning system.