Gerald Boggs Posted February 15, 2018 Share Posted February 15, 2018 1 hour ago, SLAG said: Prior to the mid 1,800's glass windows were made by blowing a large globe of blown glass. It was then opened and flattened out. That's why glass of that era exhibits charming distortions. While more trivia then useful information, the process is still being done on a small scale somewhere in Europe. Don't remember where, it was an article on sources for historical restorations. Quote Link to comment Share on other sites More sharing options...
JHCC Posted February 15, 2018 Share Posted February 15, 2018 Sweden. Quote Link to comment Share on other sites More sharing options...
Charles R. Stevens Posted February 16, 2018 Share Posted February 16, 2018 Wouldn’t a shorter ceramic pipe supported buy a wooden pipe work? The technology to make blow guns has been around and around this world a long time. This would also alow for a shorter iron pipe as well. As to window glass, I have contemplated gallon pickle jars as a way to get period looking glass with out the price Quote Link to comment Share on other sites More sharing options...
HammerMonkey Posted February 16, 2018 Share Posted February 16, 2018 6 minutes ago, Charles R. Stevens said: As to window glass, I have contemplated gallon pickle jars as a way to get period looking glass with out the price I think you are onto something there Charles. I’d like to see how that would turn out. Quote Link to comment Share on other sites More sharing options...
SLAG Posted February 16, 2018 Share Posted February 16, 2018 Mr. Shedd, requested references for the beginning use of glassblowing blow pipes. Here is one reference. https://en.wikipedia.org/wiki/Roman_Ghirshman which states that, "The earliest evidence of glassblowing was found by Roman Ghirshman in Chogha Zanbil, where many glass bottles were found in the excavations of the 2nd millennium BC site..." This site is in Iran near kharg Island or Khuzistan. (in the 1940's). I have misplaced the other reference that had evidence but will continue to search for it. (annoying that, because I read the reference earlier today. (could it be early blossoming senility? I wonder.) Trivia, trivia you say? All things are trivia to a differing selection of people. I thrive with trivia. Love it. Regards to Mr. Shedd and to all the other citizens of I Forge Iron. SLAG. Quote Link to comment Share on other sites More sharing options...
gmshedd Posted February 16, 2018 Author Share Posted February 16, 2018 9 hours ago, Glenn said: Please site your reference to the iron blowpipe and the size of the blowpipe. If you mean by reference, who has said there were iron blowpipes around 1st century AD? Karol Wight in Molten Color: Glassmaking in Antiquity (2011) p. 53, and many other authors, as well. Within glass books it's so commonly repeated, almost word for word, that I began to wonder if everyone was just copying the first person to assert it as fact, without really thinking about it--that's what brought me here. As for the dimensions of the original iron blowpipes, I can't be certain, but current blowpipes are about 3/4" x ~5 feet. The length is a matter of being long enough to be away from the heat. I thought a cruder forged iron pipe would probably have a larger diameter. Quote Link to comment Share on other sites More sharing options...
Glenn Posted February 16, 2018 Share Posted February 16, 2018 Thank You for the reference. Quote Link to comment Share on other sites More sharing options...
gmshedd Posted February 16, 2018 Author Share Posted February 16, 2018 On 2/15/2018 at 11:39 PM, SLAG said: Here is one reference. https://en.wikipedia.org/wiki/Roman_Ghirshman I don't find the quote above at the link provided, but I do find it in the Glassblowing page on Wikipedia, under History: Origins (https://en.wikipedia.org/wiki/Glassblowing). Six sentences after the sentence you quote, the section labeled "In the Roman Empire" begins with this sentence: "The invention of glassblowing coincided with the establishment of the Roman Empire in the 1st century BC." It is this later period that is generally accepted in the glass history books as the time when glassblowing was invented. I can certainly understand the confusion based on how the Wikipedia page is written. Quote Link to comment Share on other sites More sharing options...
SLAG Posted February 16, 2018 Share Posted February 16, 2018 Wiki professor Girschman. Also, read the latter portion of the cited Wiki article, to the section discussing the said professor's discovery and his findings. SLAG. p.s. Where are you located? Quote Link to comment Share on other sites More sharing options...
Charles R. Stevens Posted February 16, 2018 Share Posted February 16, 2018 It would take a bigger gasser than I have, I knew a lady who did stained glass lampshades with custom curves she did in a kiln. This is what got me thinking about using pickle jars for small panes as seen in early American multi light windows. We are constantly surprised buy the quality of early Iron Age works, so I wouldn’t make an assumption as to the quality of their work being crude or nesesitating larger diameters. Because of the cost of the material (taking huge numbers of man hours to gather and prepaid the ore and charcoal then Smelt and refine the bloom) they could afford to spend the time to do high quality work. Quote Link to comment Share on other sites More sharing options...
gmshedd Posted February 16, 2018 Author Share Posted February 16, 2018 26 minutes ago, SLAG said: Wiki professor Girschman. Also, read the latter portion of the cited Wiki article, to the section discussing the said professor's discovery and his findings. When I follow the link to the Roman_Ghirshman wikipedia page, I find no mention of glass, although all but one of the cited articles on that page are in French language journals, so I might be missing something. I also find, at the top of that page, just beneath his name, Page issues-This article needs additional citations for verification (December 2009). When I follow the link to hyperlinked Chogha Zanbil page, the only mention of glass is as "ornaments of faïence and glass." All of Ghirshman's articles referenced on this page are in French, except a 1961 Scientific American article. When I reread the Glassblowing wikipedia page, the only text regarding Ghirshman's finds of glass is that which you originally quoted above, which is supported by two references (18 and 19). 19 is written in Persian, and 18 is in Encyclopaedia Iranica. So there may be two references, one written in Persian, and the other probably written in French, that back up the assertion in the quoted sentence that the glass bottles that Ghirshman found when he excavated a 2nd millennium BC site in Iran in the 1930's constitute conclusive evidence that glassblowing was invented in the 2nd millenium BC. The same Wikipedia article that makes this assertion, then almost immediately contradicts what it just said by also asserting that "The invention of glassblowing coincided with the establishment of the Roman Empire in the 1st century BC." Obviously, both assertions cannot be true. Personally, I hesitate to place much faith in a fact that comes from a self-contradicting Wikipedia article that can only be verified if I can find, and then read, two obscure references that are written in Persian, and, most likely, French, especially when I find no mention of this 2nd millenium BC version of the invention of glassblowing in any other book or article I've read on the history of glass and glassblowing. As I said in a previous comment, I tend to doubt accepted dogma, so maybe Elam was the birthplace of glassblowing, but it will take more than one sentence in a sloppily-written Wikipedia article to convince me. Quote Link to comment Share on other sites More sharing options...
jlpservicesinc Posted February 24, 2018 Share Posted February 24, 2018 i don't remember where I had seen it nor do I remember what the time frame was.. But I do distinctly remember seeing a copper glass blowing pipe nearly 5ft long. I had seen it in person, again I can't remember where.. I fuzzidly remember it might have been at a museum on Early Egyptian tools.. Quote Link to comment Share on other sites More sharing options...
gmshedd Posted February 24, 2018 Author Share Posted February 24, 2018 I think it's possible that someone would have tried copper pipe for glassblowing, but as someone pointed out earlier, a copper pipe would have been a bit uncomfortable to use because of its high thermal conductivity. Do you remember anything about when it was used? Quote Link to comment Share on other sites More sharing options...
jlpservicesinc Posted February 24, 2018 Share Posted February 24, 2018 It was about 8 or 10 years ago it was the person who they removed from the Egyptian history.. While I would agree conductivity would be a problem with a short pipe.. No matter how hot you got the end of a copper pipe 4ft long it won't transfer that far unless the wall thickness it great enough that some cooling source is not available.. From what I understand the furnaces used to work the older glass was fairly small compared to todays gas driven units.. you can test this with a simple copper water pipe.. It won't transfer heat that far back.. Quote Link to comment Share on other sites More sharing options...
Smoggy Posted February 24, 2018 Share Posted February 24, 2018 On 15/02/2018 at 10:57 PM, JHCC said: Sweden. They also still make sheet glass by the blown method in Birmingham UK, where they were originally taught the method by Italian artisans. Quote Link to comment Share on other sites More sharing options...
jlpservicesinc Posted February 25, 2018 Share Posted February 25, 2018 Neat video.. In a lot of the older homes here the windows of smaller sizes were the spun/blown glass but it was just knocked off so they have the center still attached and not fully flattened like in the video.. Don't see that much anymore since all the updated windows and such.. Only place i have seen that kind of glass is in/on old historic buildings like at OSV, sturbridge, ma. Or Salem cross Inn in West Brookfield, MA.. Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 25, 2018 Share Posted February 25, 2018 What a GREAT thread! Thanks for bringing us this meaty question Mr. Shedd. Please put your general location in the header, or you'll never know if an IFI member is within visiting distance. Might even be someone who has forged gun barrels. Meteoric iron artifacts predates refined iron considerably. Sky metal can be found laying in the sand after a wind storm has blown cover off it. Frozen lakes in winter is another prime meteorite hunting ground though probably ignored by BCE mid eastern cultures. Meteoric iron is probably more commonly available than native copper and probably used earlier. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Smoggy Posted February 25, 2018 Share Posted February 25, 2018 1 hour ago, jlpservicesinc said: In a lot of the older homes here the windows of smaller sizes were the spun/blown glass but it was just knocked off so they have the center still attached Half the glass panels in my front door are Bull's eye glass from the centre of spun glass panels. getting hard to find over this side of the pond these days.... Quote Link to comment Share on other sites More sharing options...
gmshedd Posted February 25, 2018 Author Share Posted February 25, 2018 5 hours ago, jlpservicesinc said: it was the person who they removed from the Egyptian history It may have been Akhenaten, originally called Amenhotep IV. He became monotheistic and made everyone become so as well. After he died, they reverted to polytheism and eventually erased his name, and that of his son, Tutankhamun (King Tut) from the list of pharaohs. If it was from the era of Akhenaten, then that would be from the last third of 14th century BC, which was about 1300 years before the advent of glass blowing. The thermal conductivity of copper is more than 6 times higher than that of iron--about 400 W/m-K for copper vs. about 60 W/m-K for iron. Perhaps enough to make a difference. Quote Link to comment Share on other sites More sharing options...
JHCC Posted February 25, 2018 Share Posted February 25, 2018 Would the thermal conductivity of a copper blowpipe be an issue if you had an assistant continually cooling the pipe with a wet rag? Quote Link to comment Share on other sites More sharing options...
SLAG Posted February 25, 2018 Share Posted February 25, 2018 Or a wooden jacket? Quote Link to comment Share on other sites More sharing options...
jlpservicesinc Posted February 25, 2018 Share Posted February 25, 2018 Again I understand the heat transfer thing.. But please just take a 3 or 4 ft long pipe and heat the end till it's red.. Your hands and or mouth will be fine at the other end.. Where the problem comes in is if you angle the pipe upwards so there is a draft created pulling the hot flame and gases into the pipe.. I actually did a lot of experimenting when I was a child and learned just holding my thumb over the pipes opening was enough to keep the heat or draft from going up the pipe.. I remember the pipe clearly as well as other glass items in the cases.. Mostly stamped or formed.. But then again as with all this stuff my memory is not what it used to be and could have easily gotten information mixed up.. Dates and such used to be very important to me and as I have matured the past occurrence or time frame has become less important as the only time there is,, Is now.. 2000 years from now they will be saying the same thing about us and will be wondering why there is such a mix of extinct technology but that forged hinge still works.. Quote Link to comment Share on other sites More sharing options...
JHCC Posted February 25, 2018 Share Posted February 25, 2018 16 minutes ago, jlpservicesinc said: 2000 years from now they will be saying the same thing about us and will be wondering why there is such a mix of extinct technology but that forged hinge still works.. On a side note, have you ever read David Macaulay's Motel of the Mysteries? It's a marvelous send-up of the whole Egyptology/Tomb of Tutankhamen phenomenon, with a future archaeologist unearthing an tomb of the ancient "Usan" culture -- actually a motel room -- and offering wildly inaccurate interpretations of the artifacts therein (for example, confusing the ice bucket with a canopic jar). Quote Link to comment Share on other sites More sharing options...
gmshedd Posted February 25, 2018 Author Share Posted February 25, 2018 6 hours ago, jlpservicesinc said: Again I understand the heat transfer thing.. But please just take a 3 or 4 ft long pipe and heat the end till it's red.. Your hands and or mouth will be fine at the other end.. Being without a pipe, or a fire, I'll take your word for it! I know that in the glass shops at the museum where I work there are two indicators: 1. They leave one end of the stainless punties (50"+ X ~5/8" solid rod) in the fire to keep them warm enough to be dipped directly into the 2100F glass. The hot ends are orange when pulled from the fire. Sometimes the gaffers even dip the hot end briefly into water before doing the gather. But the other end is cool enough to be picked up without difficulty, even after sitting there for hours. 2. There are many times when a gaffer has been working with a piece on the end of a stainless blowpipe for long enough (>10-15 minutes) that they will use a pipe-cooler--a water-filled tray about 2 feet long with cutouts at each end for the pipe to drop into, that allows them to submerge the center section of the blowpipe (where they hold it) without affecting the piece on the end. Where the problem comes in is if you angle the pipe upwards so there is a draft created pulling the hot flame and gases into the pipe.. I actually did a lot of experimenting when I was a child and learned just holding my thumb over the pipes opening was enough to keep the heat or draft from going up the pipe.. Luckily for glassblowers, this is seldom a problem because as soon as they gather glass on the end of the blowpipe, that seals the passage so that air doesn't freely flow while they are working with the piece. I remember the pipe clearly as well as other glass items in the cases.. Mostly stamped or formed.. But then again as with all this stuff my memory is not what it used to be and could have easily gotten information mixed up.. Our museum has glass artifacts from the time of Akhenaten (about 1335 BC), including one that is a molded glass image of his face. The artifacts we have are pressed, or cast, but none are blown. I have read of copper pipe from an Egyptian tomb of about 2500 BC, but haven't see it in the flesh. Dates and such used to be very important to me and as I have matured the past occurrence or time frame has become less important as the only time there is,, Is now.. 2000 years from now they will be saying the same thing about us and will be wondering why there is such a mix of extinct technology but that forged hinge still works.. I was never very interested in history myself, but learning about the ancient items in our museum has piqued my curiosity about some of the details of the time in which they were made. jlpservicesinc, thank you adding to the conversation. I added some comments that may, or may not, be of interest, beneath your comments above. Do you remember the name of museum where the Egyptian items were displayed? Quote Link to comment Share on other sites More sharing options...
jlpservicesinc Posted February 25, 2018 Share Posted February 25, 2018 JHCC - Its funny to think that way, but see it totally.. Back in the day 30 years ago.. there were a lot of blacksmithing tools that used to come up for auction.. At that point I was all book smart and had worked at a lot of different facets of the General blacksmithing quota.. Wagons, hardware, tools etc, etc and it seemed there weren't a lot of people interested in Farm or agricultural blacksmithing.. Seems a lot of it was based on fancy ironwork and even really fancy hardware.. Anyhow it was a unique perspective as some of the guys at the auctions would say.. What is that or what is this.. And I actually knew because of the type of work I was doing.. I have axe and hammer making tongs which were pretty rare even back then.. My point is.. Unless you know a person using the tools or know how to use the tools it become speculation, until the methods have been proven.. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.