(Part II, Part I in September, 1988)

All American insulators have very distinctive threads: two rectangular outlines appear on opposite sides of the pinhole and there are no threads in the top quarter of the pinhole. Occasionally there will be a dot visible above the rectangle, in the unthreaded portion. Several unembossed pieces have been attributed to American because they have the characteristic American threads. These include CD 105, 126.3, 134, and 134.4. There are also two pieces embossed with only patent dates that have these threads. They are CD 156.1 embossed with only PAT. SEPT. 13, 1881; and CD 156.2, embossed on the inner skirt PAT. OCT. 15, 1872. 

One of the great mystery insulators: CD 156.2, embossed with the October 15, 1872 date and produced with American-style threads

American Insulators: CD 105, 126.4, 134 and 145

The latter is an extremely scarce item and may possibly be a prototype product made during the years just after Bay State Glass Company ceased production. These pinhole lines have been attributed to a collapsible plunger, which many believe to be the January 1, 1884, Edward J. Murphy patent or the two October 7, 1884 patents granted to Lawrence Gray, all of which were used by Gray's National Insulator Company in their production. However, Oakman was granted a patent on September 9, 1884, covering a collapsible plunger and in viewing the patent drawings, this is undoubtedly the process used to produce the Americans. A CD 105 is even used in the illustration. It seems unusual, though, that this date is not embossed on any insulators. The close similarities between the patents, plus the fact that both National and American were located in the same building in Boston and produced rim embossed insulators seems far too extraordinary for coincidence. The main link may be Edward Murphy, who is listed in the directories as a mold maker with no company association. He probably made the molds for National, and possibly American, Standard Insulator Company, and Oakman Manufacturing Company as well. That might help explain the similarities between the insulators.

American Insulators: CD 156, 156.1 and 160.7 

Unembossed Americans: CD 126.3, 134 and 134.4

American Insulator Company probably folded in late 1886 or 1887. For the next few years, Samuel Oakman is listed in the Boston Directories as a dealer in various bottles and insulators. Probably the CD 134 embossed OAKMAN PAT. SEPT.13, 1881 was made at this time, using a reworked American mold. The unembossed units with American threads may also have been made at this time.

In 1890 Oakman Manufacturing Company appears in the Boston Directory with an address at 219 State Street, the address of Samuel Oakman's previous glass dealership. The works was located on Mercer Street in South Boston. The advertisements mention bottles, carboys, demijohns and insulators, and show an illustration of the CD 145 beehive. Also, during this period Oakman was granted several more insulator patents. First was the August 19, 1890 patent for rings or threads on the inside surface of the insulator skirt to help improve insulating qualities. The June 15, 1890 patent for rings or threads on the inside surface of the insulator skirt to help improve insulating qualities. The June 15, 1890 patent was issued for the familiar cable or saddle groove insulator still popular today. Third was the May 12, 1891 patent for an insulator with one or more eyes to secure the tie wire, which became known as the Columbia.

Oakman Manufacturing Company produced mostly high voltage styles for the CD cables used for streetcars and subways. Embossed Oakman, pieces are found in CD 140, 259, 263 and 269. Another probable product of the company is CD 144.5, embossed with only the 1890 patent. Because the CD 134 was made in a reworked American mold, and it is only embossed OAKMAN and not OAKMAN MFG. CO., it was probably made earlier, in the years just after American folded.

Oakman Manufacturing Company's two varieties of Jumbos: CD 140 and CD 269

More products of Oakman Manufacturing: CD144.5. 263 and 259

Two varieties of Postals produced by American: CD 156 and CD 156.1

During his career in the glass business, Oakman was issued a great many other patents for various types of bottle-related equipment, such as packing cases, bottle molds and covers, splint machines, etc., which are included in the accompanying list of Oakman patents. In all probability many of these items were in production and may even be in the hands of collectors today.

Although a century has passed since most of Samuel Oakman's patents were issued, insulators have changed very little. Porcelain pin types produced today utilize Oakman's double petticoat and cable groove. Samuel Oakman left his indelible mark on the insulator world in a way no others who preceded him or followed him have. His influence remains even today.

A very special thanks to several people who made this article possible. Dick Bowman, Ray Klingensmith, Joe Maurath, Tom Moulton, Paul Snell, N.R. Woodward, the Boston Public Library, the Rochester Public Library and the United States Chamber of Commerce.