Hemingray Glass Company
Cincinnati, Ohio (1848-1852)
Covington, Kentucky (1852-c.1890)
Muncie, Indiana (1888-1933)
Muncie, Indiana (1933-1972) [Owens Illinois Glass Co.]
Hemingray Glass Company is the best known and was the most prolific glass insulator manufacturer in the world. Although best known for their electrical insulators, Hemingray also produced many other glass items, including bottles, fruit jars, pressed glass dishes, tumblers, battery jars, fishbowls, lantern globes, oil lamps, and much, much more.
Hemingray operated under several slightly different company names during it’s long history, first as Gray & Hemingray (1848-1856), then Gray, Hemingray & Bros. (1857-1860), Gray, Hemingray & Brother (1861-1863), Hemingray Bros. & Company (1864-1867), R. Hemingray & Company (1868-1869), and finally incorporating as the Hemingray Glass Company, Inc. in 1870.
Hemingray began as a small operation in Cincinnati in 1848. In 1852 the actual glasshouse operation was moved across the Ohio River to Covington, Kentucky, but the business office/showroom remained in Cincinnati until 1881, when it too was removed to a new building in Covington.
With the explosion of manufacturing concerns during the 1880s in the “natural gas belt” of central Indiana & northwestern Ohio, a new glass manufacturing facility was built in Muncie, Indiana and production commenced there in September of 1888. The exact year when actual insulator production ended at the Covington site is still undetermined, but it was likely sometime in the 1890-1894 period. The Covington factory also re-opened for a short time in the 1900-1902 period. The business offices remained at Covington until 1919, at which time all operation was moved to Muncie.
In 1933 the Muncie factory officially became the “Hemingray Division”, a subsidiary of the Owens Illinois Glass Company (factory #26), but insulators made after that year continued to carry the “HEMINGRAY” name. Date codes were embossed on most insulators made after 1934, and the majority (but certainly not all) of post-1934 production was made in clear (colorless) or off-clear glass.
Glass building blocks, a major item made for many years, was discontinued in March of 1966 and production of insulators was discontinued in 1967….. although the factory continued to produce television face-plates until closing permanently in 1972. (The very last glass insulators made were produced at the Indiana Glass Company factory located in Dunkirk, Indiana, using molds that had been moved from Muncie to that location).
Embossings on Hemingray-produced electrical insulators include “PATENT MAY 2 1893”, “PAT DEC 19 1871”, “H.G.CO.”, “HEMINGRAY”, “LOWEX” , “KIMBLE”, and others. The earliest insulators made by Hemingray have not been specifically identified but would almost certainly be circa 1850s threadless or possibly “Wade” types. Lightning rod insulators, and various sizes of spool insulators were also made.
In 1921, the “Hemingray-42” style insulator was introduced which was an update/replacement for the Hemingray NO. 40 insulator. (The No. 40 had been in heavy production since 1911, for telegraph lines). The “new and improved” #42 model very quickly gained in popularity for standard open-wire communication lines, and was soon the most popular and common insulator made for both telegraph and telephone lines. Many railroad lines used them for their telegraph communications, and the style became the standard for A T & T long distance “toll” lines. The 42 is classed as a “CD 154”, in the “consolidated design” cataloguing/identification system used by insulator collectors. Each CD number is assigned to a basic shape (profile/size), regardless of the exact embossed lettering, glass color or base type.
The HEMINGRAY-42 is almost certainly the most common glass insulator ever manufactured and used in the United States. (The Hemingray No. 9 is considered by some to be the most common insulator, but I think the 42 has a slight edge). The Hemingray No. 9 style was produced from about 1892 to 1955 (63 years) and tremendous numbers were used across the country on local telephone line systems. Alot of the earlier 9s had already been dismantled, destroyed or discarded (from line upgrades as well as ice storms, windstorms, fires, BB gun vandalism, etc) long before the insulator-collecting hobby started to become popular in the mid-1960s, so it is harder to make a direct comparison on total numbers ever made, since so many 9s were already in dumps and landfills before the wholesale dismantling of the railroad telegraph lines was fully underway during the 1970s-1990s. So, today the 42s are much more commonly found in such places as antique malls and flea markets.
The earliest Hemingray-42s have sharp drip points, which are believed to have been phased out approximately 1923 or 1924. The RDP (round drip point) version probably came into production sometime in 1924, although admittedly that is just an “educated guess”. Tremendous numbers of Hemingray-42 insulators with RDP bases were made, for the most part in aqua or “Hemingray Blue” (a richer blue-aqua made by Hemingray, as well as Ball Brothers, maker of the “Ball” fruit jars) during the 1924-1930 period.
The transition to off-clear glass began approximately 1930. By 1933 virtually all Hemingray-42s were being made in off-clear, very pale “ice blue”, or clear glass. Date codes were began to be implemented around 1933 or shortly afterward, that being the year that Owens-Illinois acquired ownership of the Hemingray facility. Judging from date codes, “Ice blue” (an off-clear with a faint bluish-gray tint) seems to have been made a lot during the year 1935. The majority of clear and off-clear glass Hemingray-42s (from the years 1934 to 1961) carry mold/date codes. Typically, the first number (before the dash) represents the mold number, the second number (s), after the dash, indicates the year the mold itself was made. Any dots (if present) after the second number is added to find the year the insulator itself was molded. For example, 12-41::: [six dots] would indicate an insulator made in 1947 from mold # 12. However, not all 42s have this type of date code, especially some of the earlier units dating between 1930-1940. For more information, please see a query I received which is posted near the bottom of this page.
The 42 continued in production until at least 1961, as that is the latest date code seen (so far). If you know of a Hemingray-42 which was made later than 1961, please contact me with the exact date code information!
As stated earlier, the Hemingray-42 is probably the most common U.S.-made glass electrical insulator in the world. The great majority are found in aqua, Hemingray Blue or clear glass. Less common are examples in shades of true green (i.e. showing no blue influence in the color) or in two-tone (half aqua, half green). A few examples are known in carnival glass, white milkglass and opalescent (cloudy off-white). It is likely that at least one Hemingray-42 can be found in nearly every large antique mall in the country. Even accounting for their commonness, nevertheless these are authentic relics of a bygone era in America, and will soon be true antiques. (Officially, an antique is an object at least 100 years old……..that status will be reached in 2021) .
Hemingray is well-known among antique fruit jar collectors for several types of jars they manufactured in the mid-late 1800s and up into the early 1900s. The most famous of those would be the “GLOBE” brand fruit jar which is found in a range of colors, including, of course, many shades of aquamarine, as well as several shades of amber including honey amber, yellow amber, orange amber; also olive green, blackglass, clear and cornflower blue.
Tremendous numbers of insulators embossed with the lettering “PATENT / MAY 2 1893” were made from 1893 through at least 1910, (i.e. the period of 17 years during which the patent for Hemingray’s “drip points” along the base of the insulator was in effect), and probably even for several years afterward on a few insulator styles.
NOTE: for a basic list of glass factories in the United States that are believed to have made glass insulators at some time in their history, please go to the “Glass Insulator Manufacturers” page.
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[Info sources for this page: Bob Stahr; David Dale; Clarice Gordon; Glenn Drummond; Alice Creswick (The Fruit Jar Works); various articles in Crown Jewels of the Wire magazine].