Insulator Historical Timeline! 1900-1909

Key events are noted by approximate date.  Hyperlinks will provide additional information.  Please feedback additional key dates or note any needed corrections.  Dates considered particularly significant are highlighted in red.

• 1900:  An eight mile elevated section of Boston's transit system was constructed.  Heavy DC cables were required and this line used CD 267 and CD 267.5 insulators without tie wires.  The weight of the cable was sufficient to hold it in place below  the tracks.
• April 10, 1900:  Henry M. Brookfield and Seraphin Kribs, of New York, NY patent for an automated insulator press.  This patent was assigned to the Brookfield Insulator Co. (US Patent 646,948) -- [Full Patent Text]
• May 29, 1900:  Fred M. Locke patent for the unique eves-trough design of a power insulator.  This patent was implemented in the very classic glass and porcelain combination multipart M-2795 as well as M-2796, M2785, M-2335, M-2335A and M-2336.  (US Design Patent 32,741) -- [Full Patent Text]
• December 18, 1900:  Richard H. Sterling of Pittsfield, MA patent for a multipart insulator with an eves-trough that was implemented in M-2795.  This patent was filed earlier than Fred Locke's May 29th design patent and there is an interesting story about this in Elton Gish's book: "Fred M. Locke, A Biography".  (US Patent 664,301) -- [Full Patent Text]
• December 25, 1900:  Edward Renault of Waldo, FL patent of a no-tie insulator with a screw cap to hold the wire.  The patent drawing is similar to CD 207 although there are a whole slew of similar patents which I have not listed.  (US Patent 664,432) -- [Full Patent Text]
• February 9, 1901: "The National Glass Budget" reports The Novelty Glass Co. was incorporated at Bridgeton, NJ during the past week and will take over the Gilchrist jar plant at Elmer, NJ.  Later reports show glassmaking started in early March on machine made bottles, insulators, battery jars and ointment cups.
• February 12, 1901:  Charles K. King of Mansfield Ohio patent for a mine insulator and pin.  (US Patent 667,882) -- [Full Patent Text]
• March 12, 1901:  Lewis B. Stillwell of  Niagara Falls, NY power insulator design patent implemented in U-966, U-966A, U-966B, and M-2342. (US Design Patent 34,211) -- [Full Patent Text]
• March 12, 1901: Morton Harloe patent for a no tie insulator design that uses two finger like projections around a larger wedge to hold the conductor wire.  (US Patent 669,691) -- [Full Patent Text]
• April 13, 1901: "The Commoner & Glassworker" reports The Novelty Glass Mfg. Co., Elmer, NJ, are only doing experimental work on insulators on a specially constructed machine.
• April 30, 1901:  Fred M. Locke patent for a large flat top shell for a multipart insulator (US Design Patent 34,450) -- [Full Patent Text]
• June 11, 1901:  "The Trenton Times" reports that a suit has been filed by William Brookfield against the Novelty Glass Company, of Elmer, NJ, for infringing a patent for the making of screw insulators.
• June 25, 1901:  Harry Ethridge of McKeesport, PA patent for locking insulator and pin.  Implemented in U-376, U-376A, U-376B, U-376C, and U-376D.  (US Patent 676,881) -- [Full Patent Text]
• November 12, 1901:  Ralph G. Hemingray patent for a unique top-mounted under hung high voltage insulator.  In many ways this is similar to the Beal's patent (Oct. 10, 1899) but made in two parts.  (US Patent 686,609) -- [Full Patent Text]
• February 8, 1902: "The Commoner & Glassworker" reports the Harloe Insulator Co. was organized last week at Hawley, PA with Morton Harloe as general manager. The new company propose to manufacture Harloe's self-tying insulators and other glassware.
• April 5, 1902: "China, Glass & Lamps" reports A new bottle factory is being erected at Pleasant City, O., by Burt & Bodine. It will be a 12-ton tank capacity.  This will be the Ohio Valley Glass Co.
• April 26, 1902: "The National Glass Budget" reports The Sterling Glass Co., of Elmer, NJ, was incorporated last week and will make glass at the Old Elmer Works, Elmer, NJ.
• April 29, 1902: Fred M. Locke patent for a porcelain sleeve to protect insulator pins.  (US Patent 698,976) -- [Full Patent Text]
• May 13, 1902:  Henry F. Kretzer of St. Louis, MO for a porcelain lightning rod insulator.  Insulators matching this patent have been found.  (US Patent 699,761) -- [Full Patent Text]
• May 20, 1902:  William J. Walther of Boston, MA patent for ribs under the top skirt of power insulators to add strength.  This was implemented in CD 247, CD 301, CD 315, CD 321, and CD 333.  (US Patent 700,463) -- [Full Patent Text]
• June 10, 1902:  Vernon G. Converse patent for a stacking insulator.  This patent was implemented in the amazing glass insulator comprising CD 317.8, two CD 313 sleeves, and one CD 313.1 sleeve.  (US Patent 701,847) -- [Full Patent Text]
• June 10, 1902:  A second Vernon G. Converse patent for a similar stacking insulator.  (US Patent 701,848) -- [Full Patent Text]
• November 6, 1902: "The Cambridge Jeffersonian" reports The Ohio Valley Glass Co. operating the Pleasant City glass works will do their first manufacturing today to make glass insulators for use by telegraph and telephone companies.
• December 9, 1902:  Morton Harloe patent for a no-tie insulator using three fingers to hold the wire.  This patent has been implemented in CD 109.5, CD 206.5 and U-184.  (US Patent 715,375) -- [Full Patent Text]
• March 24, 1903: Thomas C. Duffield patent for an insulator press.  This patent was used by the Novelty Glass Co. in Elmer, NJ and was involved in the lawsuit between Brookfield and Novelty.  (US Patent 723,589) -- (second image) -- [Full Patent Text]
• April 7, 1903:  Ferdinand W. Gregory of New York, NY patent for a square wire groove providing extra support for the conductor.  This was implemented in the scarce CD 159.    (US Patent 724,848) -- [Full Patent Text]
• May 5, 1903:  Joseph R. Bell of Peckville, PA patent for a no tie design that was implemented in U-181.  Only a broken specimen is currently known.  (US Patent 726,846) -- [Full Patent Text]
• May 13, 1903:  William Brookfield died at the age of 59 years.
• May 19, 1903:  Fred M. Locke patent for the design of the M-2795 insulator.  (US Patent 728,805) -- [Full Patent Text]
• May 31, 1902: "China, Glass & Lamps" reports The Sterling Glass Co., a small concern composed of Bridgeton, NJ people, have started one furnace at the Elmer, NJ Glass Works on pressed ware.
• August 4, 1903:  Vernon G. Converse patent for a power insulator with an extended skirt base.  This patent was implemented in the two piece Muncie styles CD 303/310 and CD 304/310.  (US Patent 735,212) -- [Full Patent Text]
• August 14, 1903: "The Elmer Times" reports The Harloe Insulator Company has succeeded the Sterling Glass Co. at the old Elmer Glass Works in March and are now closed making repairs.
• October 17, 1903: "The Commoner & Glassworker" reports that a large number of insulators are being turned out by the new machines at the Novelty glass works, Elmer, NJ.
• November 17, 1903:  Edward F. Schoethaler of Longbranch, NJ patent for a unique insulator design.  The drawings look very similar to the recently found "Spaceman" CD - The intent was to provide extra protection from a wire coming undone which may indicate that this idea influenced  the rare CD 139 Brookfield "Combination Safety" insulator.  (US Patent 744,631) -- [Full Patent Text]
• December 19, 1903: "The National Glass Budget" reports the Novelty glass works, Elmer, NJ, has been closed due to a suit by William Brookfield claiming that the machines used here were a patent infringement which was decided at length against the Novelty company
• January 2, 1904: "The Commoner & Glassworker" reports the Novelty Glass Works, Elmer, NJ,  plant has been closed several weeks on account of a law suit, but business will be continued as soon as the factory at the lower end of the town, recently purchased by Jonathan W. Parker, of Bridgeton, NJ, can be ready, and then make insulators.
• January 30, 1904: "China, Glass & Lamps" reports the newly organized Elmer, N.J., Glass Co., last Saturday purchased the Novelty glass factory. The latter plant has been closed since the courts decided in favor of the Brookfield Co., of Brooklyn, who claimed an infringement of patent on insulator machines,
• April 26, 1904: Scott Cutter patents the unusual CD 1038 glass Cutter tree insulator. (US Patent 758,175) -- [Full Patent Text]
• June 11, 1904: "The Commoner & Glassworker" reports The Ohio Valley Glass Co., Pleasant City, OH., have resumed operations again, but the company has been reorganized, only retaining the same name making pressed insulators.
• November 26, 1904: "The Commoner & Glassworker" reports an injunction issued against the Elmer Glass Works restraining them from using an insulator press designed by Thomas C. Duffield (US Patent 723,589) as it is an infringement the Kribs patent (US Patent 646,948). The decision of the court on this preliminary motion does not finally determine this question, but leaves it to be determined at the final hearing of the case.
• January 19, 1905: "The Cambridge Jeffersonian" reports that the Ohio Valley Glass Company, of  Pleasant City, OH, is in receivership.
• April 1, 1905: "The Commoner & Glassworker" reports the new invention of Morton Harloe for the manufacturing of glass insulators was tested at the glass factory Wednesday evening by members of the Harloe Insulator Co.  We understand that an offer was made for the invention after it was tested, but it will not be sold unless the plant goes with it.  These were undoubtedly the no-tie styles CD 109.5 and CD 206.5.
• August 29, 1905:  William R. Twiggs of Sandusky, OH patent for a no-tie insulator using a top groove and a set of glass balls (or marbles) to slide into the groove clamping the tie wire.   This was implemented in the super rare CD 141.7 insulator.  (US Patent 798,235) -- [Full Patent Text]
• October 10, 1905: Anthony Kribs of Brooklyn, NY patent for an insulator press designed to make complex shaped insulators such as the CD 139 combination safety which is illustrated in the patent.  (US Patent 801,461) -- [Full Patent Text]
• August 1, 1906:  Trustees of the Ohio Valley Glass Company sold property and real estate in Pleasant City, Guernsey County, Ohio,  to the Hemingray Glass Company.  Link for additional Hemingray information.
• August 8, 1906: "The Newark Daily Advocate" reports that the Ohio Valley Glass Company, of Pleasant City, OH, has been sold to the Hemingray Glass company.
• December 11, 1906:  Frank G. Baum of San Francisco patent for an unusual multipart insulator that included an auxiliary porcelain tube as well as many small petticoats or rings on the underside of the insulator.  Although there is no record of the auxiliary tube being used,  The rings have been implemented on some of the Large M-4600 Lima and Thomas styles. (US Patent 838,163) -- [Full Patent Text]
• October 8, 1907:  John C. Barclay of New York, NY patent for an insulator with an external spiral groove opposed to the internal threads to allow insulator replacement without removing the tie wire.  This patent was implemented in CD 110, CD 147, and CD 150.  I've never been sure why this was not pre-dated by the Dec. 25, 1883 patent for a similar idea.  (US Patent 867,901) -- [Full Patent Text]
• March 17, 1908:  Charles R. Slusser of Montpelier, ID patent for an unusual top groove insulator implemented in the rare U-185 porcelain insulator.  (US Patent 881,967) -- [Full Patent Text]
• March 24, 1908:  Leonard W. Storror of San Francisco, CA patent for an insulator with an insert to improve insulation by making a better barrier to moisture.  This was implemented in the Brookfield CD 211 "No Leak" insulator.  (US Patent 882,803) -- [Full Patent Text]
• May 26, 1908:  Chauncey C. Johnson patent for a no-tie insulator design.  This patent was assigned to John Watson and was implemented in CD 109.7.  (US Patent 888,616) -- [Full Patent Text]
• July 28, 1908:  John L. Fay of St. Louis, MO patent for a insulator and wire clamp.  This patent was implemented in porcelain insulator U-401.  (US Patent 894,616) -- [Full Patent Text]
• January 12, 1909: Ralph G. Hemingray and Charles Hawk, both of Muncie, IN patent for an automated insulator press.  (US Patent 909,595) -- (Additional Patent Image) -- (Third Image) -- [Full Patent Text]
• April 6, 1909: Charles E. Eveleth of Schenectady, NY patent for a porcelain power insulators with skirt grooves to allow pieces to break off if hit by a projectile preventing the loss of the whole insulator.  This patent was implemented in the rare M-2202 and M-2202A porcelain power insulators.  (US Patent 917,031) -- [Full Patent Text]
• August 3, 1909:  Joseph H. Ranson of Batavia, OH patent for a no-tie, twist lock  porcelain insulator implemented in U-183.  (US Patent 929,878) -- (Second Image)-- [Full Patent Text]

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