Machine bottle forming: gob feeders, the Lynch machine, blow-and-blow vs the Owens suction machine

Sources: SHA “Machine-made Bottle Dating” (https://secure-sha.org/bottle/machinemadedating.htm); Emhart Glass “Making Glass Containers”; Encyclopedia.com “Lynch Corporation” (https://www.encyclopedia.com/books/politics-and-business-magazines/lynch-corporation); Hartford-Empire Co. v. United States. Ingested: 2026-07-26 (agent research).

The gob feeder (Hartford-Empire “feed-and-flow”)

Molten glass flows from the furnace forehearth into a feeder bowl; a plunger rises and falls, forcing glass down through a narrow orifice as a controlled stream, which a mechanical shear cuts into a precisely sized, precisely timed gob. The plunger-feeder design “has not changed since it was launched by Hartford-Fairmont (forerunner of Emhart Glass) in 1918.” Reliable gob feeders (c.1915+) converted cheaper semi-automatic machines into fully automatic ones, and — crucially — gob-fed bottles never show a suction scar (they are not formed by suction). This feed-and-flow approach, licensed by Hartford-Empire, came to dominate the industry in the 1920s.

The Lynch machine

Lynch Glass Machinery Co. (Anderson, Indiana, founded 1917) made semi-automatic bottle machines and, in 1923, a fully automatic rotary machine able to form both narrow-neck and wide-mouth ware. Lynch was an independent maker (Hartford-Empire’s principal competitor, later paired under license), which is why the Three Rivers brochure names “a gigantic Lynch machine and Hartford-Empire feeder” together — the Lynch forming machine fed by the Hartford-Empire gob feeder. The machine’s molds “revolve continuously” on a rotary table.

Blow-and-blow (narrow-neck beverage bottles)

1. Gob drops into a two-piece blank (parison) mold.
2. Settle blow / counter-blow: compressed air first blows the gob down to form the finish (the sealing mouth/threads) precisely, then a counter-blow forms the rest of the parison — an elongated blank with the finish already fixed.
3. Transfer & reheat: neck-ring/transfer arms invert and move the parison to the blow mold on the revolving table.
4. Final blow: compressed air blows the parison against the two-piece blow mold’s interior walls (which carry the die-cut embossing), completing the shape.
5. Ejection: the mold opens; a takeout carries the bottle to the lehr. At Three Rivers this whole cycle took “twenty seconds.” Diagnostic trace: faint ghost seams on neck/shoulder.

Press-and-blow (wide-mouth milk bottles / jars)

For wide-mouth ware a plunger presses the gob into a one-piece blank mold to form the parison (rather than blowing it), then transfers it to a blow mold for the final blow — leaving a round valve mark on the base. “Milk Bottle machine” was industry-wide shorthand for exactly this class of wide-mouth press-and-blow rotary machine; Three Rivers’ separate “giant milk-bottle machine” fits this. SHA documents a “Lynch Milk Bottle machine” 7-stage press-and-blow cycle.

Contrast: the Owens suction machine, and the later IS machine

• Owens machine (1905+): needed no feeder — it sucked metered glass directly up out of the tank into its parison molds by vacuum, shearing at the base, leaving a feathered suction scar impossible on gob-fed ware. Capital-intensive and tightly patent-controlled; the cheaper gob-feeder + rotary machine displaced it in the 1920s. (Three Rivers used gob feeders, NOT the Owens machine.)
• IS (Individual Section) machine (Henry Ingle, Hartford-Empire, 1925): replaced the single revolving rotary table with independent stationary “sections” fed in sequence, each running its own cycle — sections serviceable without stopping the whole machine. It superseded rotary Lynch-type machines through the 1930s. Three Rivers’ brochure describes the older rotary architecture — mid-1920s state of the art, on the cusp of being superseded.