locked Re: Drawing and Maps in the SRHA Archives
Andrew:toggle quoted messageShow quoted text
One of the first things we show visitors to the archives are examples of our ink-on-linen drawings. When I explain they are high thread count linen cloth coated with starch then drawn on using ink pens, I’m never sure if I am believed. College students tell me they have never seen similar drawings. The twenty-six foot long drawing of John Sevier yard I mentioned was several pieces of linen spliced together and then used for the drawing. The SRHA archives contain hundreds of linen originals, some dating to the 1880s that are in perfect condition. Some early versions of ink on Mylar suffer from separation between the Mylar base and the coating that holds the ink. Even moving one of those drawings can result in a blizzard of flakes as more of the top layer detaches.
We also have many whiteline and blueline prints. If they are not exposed to light, they hold up well except many were folded and stored in file cabinets for years. The folds become quite dark and are hard to scan. Sometimes the folds become so brittle, opening them is difficult.
It has not happened often but there are times when we realize putting a drawing in a carrier (a plastic sleeve) and running it through the scanner might damage it beyond further use. Our logic (some may disagree with) is that in most cases we do not consider a drawing as an artifact. It is the information on the drawing that we can preserve with the best quality scan we can make.
PS We also show people some of the hundred thousand or so drawings on microfilm aperture cards in the collection. The 35mm microfilm is mounted in standard (circa 1960s) IBM 80 column Hollerith punch cards that could be sorted and the punches read. (I was carrying a tray of them in the elevator at NS one day when some IT people asked what they were. I pulled one of them out, showed them how the punches were laid out and told them they were the new way we would be storing data. The door opened and I stepped out leaving them wondering what I was up to.)
On Apr 4, 2021, at 6:01 PM, aramsay18 <aramsay37@...> wrote:
Such old engineering artifacts are not seen very often and are highly respected for what they represent.
I just want to point out that aside from its historical significance, this drawing is a strikingly excellent example of engineering mechanical drafting/drawing state-of-the-art practice in the 1940s to late 1970s. It is a what-if markup of an existing blueprint. It appears to be all hand drawn (using various drafting instruments such as french curves, possibly customized french curves, large radius compasses, etc.) from tables of survey data. The person or persons who prepared this document spent many, many hours, more likely many weeks, working to first draw it, then to validate it. He would be given a design, perhaps at the top level, and would be expected to take it to the detailed level shown. He would have to have significant operational knowledge of how the rail layout should work to meet a complex set of functional requirements which change over time as rail operations progress. Drawing and validating this layout would require painstaking, meticulous work by hand to fit curves to the survey data and to ensure the fit was highly accurate as to the actual layout. A senior designer and draftsman, a highly respected engineering professional, would have supervised its preparation, and possibly done much of it himself. Not to mention this is a blueprint. The original would have been prepared on a vellum surface (like parchment) or high-grade paper using India ink. Mistakes in that media would be wiped off with an alcohol/water mix or scraped off with a razor blade. The original would have taken months of work.
Nowadays this would all be generated using computer-based tools. The curve fitting to match the digital survey data would be generated in a few minutes on a PC-scale computer. Any misfits would be easily adjusted graphically. This quick cycle would enable many iterations of what-if drills to optimize the layout to its corresponding requirements. It would also enable collaborative reviews for approval. The tabular form would be taken directly from highly accurate digital survey data collected on the ground, possibly supplemented by overhead imagery to include LIDAR to show elevation data. There is an impressive contrast in engineering productivity over almost 80 years.
Were these proposed changes/additions implemented?
On Sat, Apr 3, 2021 at 9:52 PM George Eichelberger <geichelberger@...> wrote:
We don’t post many drawings or maps to the .io group simply because so many are quite large. Here’s one @ 207M fits that category. It’s from file discussing the expansion of Cincinnati Union Terminal in 1943. There are several CUT files in the archives starting with an early plan to build “Cincinnati Union Station”. Something certainly worth of research and a TIES article?