ALBANY, N.Y. (AP) — A modern-day glassblower believes he has unraveled the mysteries of Renaissance-era Venetian glassmaking, a trade whose secrets were so closely guarded that anyone who divulged them faced the prospect of death.
Today's glassblowers work with methane-fired furnaces, electric-powered kilns, good lighting and proper ventilation. The craftsmen of Murano, an island near Venice, didn't have such technology, yet they still turned out museum-worthy pieces known for their artistry and beauty, using techniques that remained exclusive for centuries.
Through years of researching Venetian glass collections at American and European museums and comparing the artifacts with more contemporary glasswork from Venice, plus his own experimentation and many trips to Italy, William Gudenrath has created an online resource he believes explains Venetian glassmakers' methods.
"The Techniques of Renaissance Venetian Glassworking" — which contains videos, photographs and text — details how Gudenrath surmises glassworkers produced works of art with little more than wood-fired furnaces and metal blow pipes and tongs. The information was posted this week on the website of the Corning Museum of Glass in upstate New York, where Gudenrath is a resident adviser and teacher of Venetian techniques.
The gilding and enameling the Murano glassmakers added to their glass products had to be fired at higher temperatures than the glass itself to make the decorations permanent. The Venetians couldn't simply turn a nob to regulate the temperature of their furnaces, Gudenrath said, yet they mastered the tricky art of glass decoration by continuously reheating and shaping the vessel after the decorations had been added, a process he demonstrates in several videos.
"It's just amazing to me that they did what they did in those conditions," he said.
Gudenrath's knowledge of Venetian glassmaking and his research into the process, something he has focused on for 25 years, are a "fantastic resource for artists," said Jutta-Annette Page, curator of glass and decorative arts at Ohio's Toledo Museum of Art.
Gudenrath, 65, became fascinated with Venetian glass while a teenager in Houston, where he started blowing glass at age 11. But finding written documents detailing how Murano glass was created proved difficult, a result of restrictions placed on the trade hundreds of years ago.
To prevent fires, the Venetian government ordered glass furnaces moved to Murano in the late 13th century. The move also was aimed to prevent secrets of the glassmaking guild from being smuggled to competitors. Anyone attempting to do so could be executed under Venetian laws created to maintain the city's monopoly on the European luxury glass trade.
"Industrial espionage and that sort of thing was taken very seriously," Gudenrath said.
Competition from other European nations eventually weakened Murano's hold, and Napoleon's closing of the factories after conquering Venice sent the industry into further decline. Venetian glass experienced a rebirth in the mid-19th century, but Gudenrath said much of the practical knowledge of the original, secretive methods had been lost.
Some of the old techniques have been reinvented and are being again used on Murano, still home to vibrant, albeit smaller, glassmaking operations and studios.
Mfumo wa kutengeneza kioo wa Venice uliotumiwa katika enzi ya Renaissance ulifichwa kwa siri sana hivi kwamba mtu yeyote aliyezifunua alishtakiwa kufa. Kwa mfano, kwa sasa, watu wanaopiga kioo hufanya kazi kwa kutumia tanuru za methane, tanuru za umeme, taa nzuri, na hewa nzuri. Wafanyabiashara wa Murano, kisiwa kilicho karibu na Venice, hawakuwa na teknolojia kama hiyo, lakini bado walitengeneza vitu vya makumbusho vinavyojulikana kwa ufundi na uzuri wao, wakitumia mbinu ambazo zilibaki kwa karne nyingi. Baada ya miaka ya utafiti wa makusanyo ya kioo ya Venice katika makumbusho ya Amerika na Ulaya na kulinganisha vitu vya kale na kazi za kioo za kisasa kutoka Venice, pamoja na majaribio yake mwenyewe na safari nyingi kwenda Italia, William Gudenrath ameunda rasilimali ya mtandaoni ambayo anaamini inaelezea mbinu za watengenezaji wa kioo wa Venice. "Ufundi wa Renaissance Venetian Glassworking" - ambayo ina video, picha na maandishi - maelezo jinsi Gudenrath conjectures glassworkers zinazozalishwa kazi za sanaa na kidogo zaidi ya oveni kuni-kuwaka na chuma blow mabomba na pliers. Utafiti huo ulifanyika katika jumba la makumbusho la Corning Museum of Glass, New York, ambapo Gudenrath ni mshauri wa teknolojia ya Venice. Kwa mfano, kwa kuwa vioo vya Murano vilitengenezwa kwa glasi, vilipaswa kuchomwa kwa joto la juu kuliko glasi yenyewe ili vioo hivyo viwe vya kudumu. "Wavenicia hawakuweza tu kugeuza ""nob"" ili kudhibiti joto la tanuru zao, lakini walipata ustadi wa sanaa ya kupamba kioo kwa kuendelea kupaka moto na kuunda chombo baada ya mapambo kuongezwa, mchakato ambao anaonyesha katika video kadhaa." "Ni jambo la kushangaza kwangu kwamba walifanya walivyofanya katika hali hizo", akasema. Ujuzi wa Gudenrath wa utengenezaji wa kioo wa Venice na utafiti wake juu ya mchakato huo, kitu ambacho amekuwa akizingatia kwa miaka 25, ni " rasilimali ya ajabu kwa wasanii, "alisema Jutta-Annette Page, msimamizi wa kioo na sanaa za mapambo katika Jumba la Makumbusho la Sanaa la Toledo, Ohio. Gudenrath, mwenye umri wa miaka 65, alivutiwa na kioo cha Venice alipokuwa kijana huko Houston, ambapo alianza kupiga kioo akiwa na umri wa miaka 11. Lakini kupata hati zilizoandikwa zinazoelezea jinsi kioo cha Murano kilivyotengenezwa kilikuwa vigumu, kwa sababu ya vizuizi vilivyowekwa juu ya biashara hiyo mamia ya miaka iliyopita. Ili kuzuia moto, serikali ya Venice iliamuru tanuru za kioo zihamishwe hadi Murano mwishoni mwa karne ya 13. Hatua hiyo pia ilikusudiwa kuzuia siri za shirika la kutengeneza glasi zisiingizwe kwa magendo kwa washindani. Mtu yeyote aliyejaribu kufanya hivyo angeweza kuuawa chini ya sheria za Venice zilizotengenezwa ili kudumisha mamlaka ya jiji hilo juu ya biashara ya glasi ya kifahari ya Ulaya. "Ujasusi wa viwanda na mambo kama hayo yalichukuliwa kwa uzito sana", Gudenrath alisema. Ushindani kutoka kwa mataifa mengine ya Ulaya hatimaye ulidhoofisha mamlaka ya Murano, na kufungwa kwa viwanda vya Napoleon baada ya kushinda Venice kulifanya sekta hiyo iendelee kupungua. Kioo cha Venice kilipata kuzaliwa upya katikati ya karne ya 19, lakini Gudenrath alisema mengi ya maarifa ya vitendo ya mbinu za awali, za siri, zilikuwa zimepotea. Baadhi ya mbinu za zamani zimebadilishwa na zinatumiwa tena huko Murano, ambako bado kuna viwanda na studio za kutengeneza glasi zenye nguvu, ingawa ni ndogo.