Call No: P500-A4
Description: Glass blowing
Date of origin:
Type: Print
Size: 8 1/8 x 10
Condition: Very Good
Content:
[front] A ; B ; C ; D ; E ; F [all letters are circled and boxed in white]
[back] Reduce to 4 1/4 x 5″ ; Return Photo To HARRY E. CHRISMAN 10245 W. 14th Ave. Denver, Colo. 80215 ; PITTSBURGH PLATE GLASS CO. PUBLIC RELATIONS DEPT. PITTSBURGH 22. PA. NEGATIVE NUMBER 4237-22 [4237-22 is underlined]
[note] Copy L-2 [Copy L-2 is underlined] ; The [insert mark] secret experiments conducted at Belle Vernon, Pennsylvania, before the turn of the century by American Window Glass Company in which C. E. Hancock participated, convinced many that sheet glass could be drawn flat from the melting tank. By 1918, Pittsburgh Plate Glass Company engineers had explored this process thoroughly and had built the machine to draw the glass vertically [vertically is underlined] from the melting tank rather than to draw it horizontally. Like thick, viscous, molasses the molten glass clings to the “bait,” flat steel bars the width of the sheet to be drawn, at the bottom of the machine. [insert mark] This cutaway photo view shows the molten sheet [insert mark] as it is fed from the bait into a series of rollers that move the solid sheet upwards. This is the Pennvernon Process. (a) conveyor belt moves (b) molten glass to [? is crossed out] (c) where it takes the “bait” and (d) the rollers gently raise the cooling sheet to (e) observation floor and on to (f) the cut-off floor where it is cut into sheets (g) [(g) is crossed out] and automatically placed on conveyor line. Photo coutesty Pittsburg Plate Glass Co. [Photo coutesty Pittsburg Plate Glass Co. is underlined]
Provenance:
Miscellaneous Info.:
Photo is of a cutaway section of a machine. There are two men working. There are letters circled with a white box around them. This aids in reading the note and telling which each process is in the picture.
Other Info.: Photo has tape and tape tear marks on top back. Photo is wrinkled on sides. Note has tape on top.
Related to: P499-A4 (Charles Hancock glassblower),
Subject: American Window Glass Company, Belle Vernon, Charles Hancock, glass blowing, Pennsylvania, Pennvernon Process, Pittsburg Plate Glass Company, Plate glass,