A History of the Consolidated Design Numbers
From Insulator Wiki (Wikilator)
NOTE: The below is a note sent to ICON by William Snell
As I reviewed the posts on this CD discussion, I realized that several people have mentioned that Woody’s CD assignments have a long history and the system has become standard throughout our hobby, but no one has really mentioned its evolutionary process in any detail. I suspect unfamiliarity with that aspect of the CDs is contributing to frustrations with using the system and some feeling that it is less than ideal.
Be forewarned: this is very long. But for those of you to whom this is not “old hat,” I hope you are willing to indulge me and read it, and perhaps you’d be kind enough to email me your comments or corrections.
While I’ve been involved in the hobby for quite a while, and the CD system is of great interest to me, bear in mind there are some more knowledgeable people who might be able to fill in some gaps in my information. Most of this is based on my own personal experience of collecting since 1980, as well as correspondence with N. R. Woodward and other collectors, as well as articles in CJ, Crossarms, and other published insulator research. And I have an archivist mindset, so the understanding development of insulator information over the years is almost as much a hobby for me as collecting insulators themselves.
As far as I understand it, Woody developed the CDs as we know them today back in the 1950s, when to his knowledge, he was the only person interested in insulator history, and his intent was to create a communication tool for correspondence between him and glass manufacturers. Woody has stated in his biography in CJ that he had developed and scrapped several CD systems to identify insulator shapes over the years, and the one we know today was his fourth or fifth attempt.
While the first edition of N. R. Woodward’s The Glass Insulator in America: A Report was published in 1965 (in commemoration of the July 25, 1865 Cauvet patent for threads), it contained only historical information and did not cover the CD numbers. The 1967 edition outlined the CD assignments with illustrations from a variety of sources, including the Brookfield catalog and other areas, and featured tabulations of manufacturers associated with each shape but had no detailed embossing data. This was the first insulator reference book I used to learn and apply CD numbers, since my local library had a copy. If one looks at it today, we can see a very logical arrangement of only integral numbers, most of which are familiar to us now. The manufacturer tabulations demonstrate very broad parameters in some CD assignments: what we know today as CD 126.4 and 126.3 were both listed under CD 126; there is a listed Pyrex CD 122, which is today’s 122.4, and others. Woody also assigned numbers to pieces based on catalog information that have never been discovered: CD 171, 172, and a host of Brookfield multipart power pieces in the 300 series, and a few others. Those items are not shown in the McDougald Price Guide that we use today, since no extant examples are known, so it appears there are some large, inexplicable gaps if one uses McDougald as a sole source. But the CD assignments exist, as published by Woody himself.
Shortly afterward, in 1967 Marion Milholland began publishing his Glass Insulator Reference Book, which he updated every few years, and his work popularized the CD numbers. His books’ prefaces acknowledge the source of the CD system, but as far as I understand things, it was Marion who changed the conception of CDs as a correspondence tool to a collector identification system. Marion was deeply involved in the growing insulator hobby, and unlike Woody, he traveled across the nation to visit collectors, attend bottle and insulator shows, and he gathered information and photos wherever he went. He found many unusual insulators people had located that didn’t fit anywhere in the CD chart. In some cases, it appeared Marion assigned his own CD numbers to pieces and then published them in his books, and it is rather difficult for a collector today to figure out which assignments were made by whom. I do know that Marion assigned all of the threadless CDs in the 700 series. By today’s standards, his research was not always what we would call exacting. Many collectors of the early years tell stories of his having scraps of paper – torn from newspapers, used envelopes, etc. – stuffed into his pockets after every insulator show, with hastily scribbled notes on new pieces to add to his books. Throughout the late 1960s and early 1970s many people published insulator collecting and price guides, but none had truly nationwide information as Milholland’s books did. His price guides became the most commonly used set of trade and sale values used in the hobby before the McDougald books.
The 1969 edition of Woody’s Report shows the first evolutionary expansion of the system, since there were not enough integral numbers available to add the new discoveries easily. We might think it as shortsightedness on Woody’s part today, but when he originally developed the system he had been collecting for many years, in several areas of the United States, and had amassed a wealth of catalog and historical data, so it’s understandable that he thought he had covered most insulators produced in the 1865-1965 period. In the 1969 edition, the system expanded into the 400 series, and I quote Woody’s explanation: “It will be noted that, where new ranges of numbers in the 400 and 500 series have been added, they are intermingled with the original numbers in the lower series. As more numbers were needed, it was thought best to use numbers from higher series, and leave the original numbers undisturbed as many persons have become accustomed to using them. As an example, CD #428 is added immediately following CD #128, to which it is somewhat similar.” (Note: what was CD 428 is now known as 128.4). Woody expanded the system to accommodate new items, and some CDs appear to have been “narrowed” in their parameters: the insulator listed as a CD 126 Am. Insr. Co. and W. E. Mfg. Co. in the 1967 Report is now listed as CD 426, and the illustration corresponds to today’s 126.4. The next Woodward Report dates from1973. We find the big change of adding decimal points to allow the system to expand and accommodate new items, and the elimination of the 400 series, but the remaining numbers are intact. Decimals offered much more flexibility than the incorporated 400-500 series of the 1969 edition. We see many pieces assigned to the numbers we know today, as well as some Australian items (124.6, 124.7, 152.9) that were later reassigned to foreign numbers in the 400 series. Now we find the insulator shape listed in 1967 as CD 126 Am. Insr. Co. and W.E. Mfg. Co., and in 1969 “CD 426,” has been changed to CD 126.4, where it remains today.
Most collectors in the hobby used Milholland’s final book dating from 1976, the same year that Marion Milholland passed away. Like most of Marion Milholland’s books, it featured full-size photos of the insulators, rather than the mechanical drawings found in the Report. As a result, collectors – myself included! -- easily confused some CDs, especially in one case where Milholland published an identical photo in two different locations, CD 127.6 and 145.6. The two pieces had the same exterior shape, but of course if one pays attention to where they fall in the sequence, one has an inner skirt and the other does not. (CD 127.6 was later reassigned to 143.6 – I believe Marion Milholland assigned the 127.6 based on the fact that it lacked the ridge just below the wire groove, which is shown in his photo for 143.6. Woody stated to me in a letter that a small ridge like that is not reason enough for a different CD, just like 127 or 128). Of course, in photos, it is often very difficult to tell if an insulator has inner skirt(s) or not. Marilyn Albers took on the task of “clearinghouse” for foreign insulator information and became foreign insulator editor for Crown Jewels in 1979. She and Woody enjoy a close working relationship, and in 1981 she published the first edition of Glass Insulators from Outside North America, which featured new CD assignments in the 400-600 series. Marilyn’s name is the only author stated on the cover, and to my knowledge this is the only insulator reference that bears the official seal of the NIA on the title page. A few years later, Marilyn announced that Woody had been responsible for organizing and assigning all the CD numbers in that book. Woody had asked that the cover not bear his name for personal reasons, but through the years following GIFONA’s introduction in 1981, Marilyn convinced him to step up and receive the credit due him. The subsequent editions of GIFONA bear both Woody’s and Marilyn’s names as co-authors, with Jack Tod (and later Elton Gish) providing the detailed mechanical drawings.
Woody published the latest version of his Report in 1988, again with Jack Tod providing high-quality mechanical drawings to replace the ones of previous editions that were culled from various sources; I believe some came from catalogs, while several different artists created others specifically for Woody’s book. This edition included FAR more illustrations than ever before, rendered more consistently than in previous editions.
John and Carol McDougald published their two-volume series in 1990, which illustrated CDs by photograph again, with new embossing listings that they began from scratch, without relying on Milholland’s work, which is an enormous task that truly never ends. In preparation for his book, the McDougalds and Ray Klingensmith held a meeting of all interested collectors at the 1989 National in Allentown, and I was one of them. They offered us two choices: a completely new set of threadless CD numbers, or keeping most of the numbers we knew from Milholland but with some rearrangement, which would naturally result in a lot of decimal points. We overwhelmingly voted in favor of the rearrangement of the familiar numbers. Ray revised the CD assignments for threadless insulators, since there had been a large number of new discoveries between 1976 and 1990. Comparing the McDougald books with earlier insulator references show us some interesting contrasts. Some insulators that Marion Milholland had photographed and featured in his books have never come to light again; while some have been proven to be mistakes. The 1976 edition of Milholland’s book shows a CD 137.4, which was later proven to be an opalescent CD 128 that someone had sawn off most of the skirt and polished to look like a whole insulator. Woody listed a CD 160.4 American Insulator Co. in the 1973 Report (with no illustration, unfortunately), and I corresponded with him about it for my Oakman-related research. The insulator was lost to the hobby for many years but resurfaced around 1995. John McDougald listed it as CD 162 in his 1995 Price Guide, and revised it in later editions, which is understandable given its rarity and the fact that CDs are interpreted by anyone who uses that system.
Since 1991, the McDougalds have published an updated Price Guide every four years. With the addition of CD illustrations in the 1999 edition, it could be used as a handy, single source of glass insulator information for many of us. So if a McDougald Price Guide serves as your one and only book you own as a collector, please be aware that there is a lot more to the CD system and the Price Guide than meets the eye. This system has grown and evolved with the hobby, and to those of us who “grew up” with it, the apparent mediocrity and illogical progression seems a very small price to pay for what we use today. Considering how much it has been adapted over the years, I think the flexibility of the current system is one of its strengths.