In your Sep. 74 issue you carried a letter I had written to you concerning insulators embossed with an RD and some numbers. I was seeking any information I could get from anyone who had or has had one in the past. Also anyone else who knew anything about them, where they came from, etc. The two insulators I was researching were CD-126 RD 149959 and CD-133 RD No. 154745.

I received only six replies, but they were all helpful.

The letter that put me on the right track was one from a Mrs. Elsie Havers out in Wenatchee, Wash. While reading her husband's insulator magazine, she saw my letter, and the RD rang a bell. Several years before she had bought an antique condiment set in Kamloops, British Columbia. On the bottom of each piece was imprinted RD 194638. The dealer who sold her the set told her that be believed it to be of British origin.

Mrs. Havers suggested I write to Dr. Arthur G. Peterson, author of several books, including 400 Trademarks on Glass. Dr. Peterson told me that British registry marks did carry an RD in the center of a diamond design surrounded by other numbers and letters to indicate year, month, day, and material used. This system was used at least from 1842-1883. This was not the same design as the embossing on the insulators, but it had me relatively sure they were Canadian or British.

I then wrote to the Patent and Trademark Institute of Canada at Ottawa, Ontario. I drew a blank here, but they referred me to British Patents Office for possible help.

In the meantime I had written to House & Garden magazine in New York. They have a column where they answer questions pertaining to antiques. I told them I had a condiment set (Mrs. Havers') with an RD 194638 embossed on it, and asked if they could tell me where it came from? During this time I was also writing to the Comptroller-General of Patents, London, England. While I was waiting for a reply from London (these correspondences took from four to six weeks each time), I received a reply from House & Garden. Mrs. Havers' condiment set had been registered at the London Patent Office in 1892. Now we were getting somewhere.

Next came the reply from London. They explained to me their system of registering designs and trademarks and how I could inspect them personally or pay an agent to make a "search" for me. The cost of having the search made wasn't that great, so I sent the check.

I asked that, if possible, he tell me who, where and when these RD insulators came from. Also, was Wm. Brookfield mentioned at all. My reason for the Brookfield question was that I believed then and still do that these insulators were somehow connected to him, legally or otherwise. I'll go into this later.

A month later some of the answers came. On May 22, 1890 a number RD 149959 was issued (for the CD-126 style) to Glass Merchant James Bridger, Mead House, Upper Edmonton, London. August 20, 1890 RD No. 154745 (CD-133) was issued to F. H. Davey & Co., Edmonton Glass Works, Upper Edmonton, London. Also sent to me were photostats of the original drawings of the insulators as they were presented for registration. They included another insulator, RD 154744 (a CD-134) which to my knowledge has not been found, at least not in this country.

They could not give me any history of the manufacturer, but did supply me with a couple of addresses I could try: Central Library, Enfield, Middlesex, and Pilkington Group Archives and Record Service, St. Helen, Lancashire. I wrote to both parties, but they could not give me anything positive concerning the history of either Bridger or F. H. Davey Co. Pilkington Archives did say that James Bridger was probably an agent for Davey Co. They searched the history of the Edmonton area around the time the insulators were registered, but could not come up with anything.

My reason for wanting to go further than just finding out where they were made is that I would like to find a connection with Brookfield. Some of the CD-126 Brookfield insulators carry a Jan 14 1879 patent, and the CD-126 W.U.T. Co. Brookfield has a Mar 20 1877 patent date. These are both design patents, and they would not have legally run out until 1894 and 1896. These insulators bearing the RD numbers were made in 1890, and they are exact copies of the Brookfields. There must have been some connection. I talked with Mr. William L. Brookfield, grandson of Wm. Brookfield to whom the patents were issued, and he believes the connection to be a legal one, as patents were pretty safe in those days.

For my last attempt at finding an answer I had another search made by a private agent on the history of Bridger and F. H. Davey. The best she could tell me was that James Bridger's firm was registered as manufacturer of glass tiles, panels and lights on 10 Nov 1886 and as manufacturers of electrical battery jars in 1889. The Davey firm does not appear to have been registered by the patent office at all, although she searched a period of over fifty years.

The CD-126 RD 149959 that I have came from New York state. A bottle digger dug up half a dozen behind a farmer's barn. There were Brookfields found with them. I know of others that have been found in Georgia and Nevada. The CD-133 RD No. 154745 that I have was dug around Mystic, Connecticut by another bottle digger. I know there has to be at least one more around somewhere, because Milholland lists it, but I don't know where it was found. The CD-126 is a real milky green. Almost a jade, if you didn't look at it more closely. The CD-133 is a clearer green, with milky swirls and lots of small bubbles. Both are ground on the bottom like old canning jars, which is unusual. Both have the mold line over the dome and the swirl start to the threads.

All the questions have not been answered, but what information I did gather sheds some light on the RD insulator. This is the first insulator I ever researched, and I can tell you I had a real exciting time doing it. I'd also like to use this space to thank everyone who helped me in this project.