I have had an old Dallmeyer lens in my possession now for a few years. It was found at a fleamarket and I had a lot of fun trying to track down when it was made and the type. I eventually settled on a manufacturing date of 1864 based on serial number (8703) and a lens type of Ordinary Portrait Lens. The search was not helped by the fact that the rear cell was no longer present but I read somewhere that portraitists often did this to soften areas outside the central portion of the image. This is now usually called " the swirly bokeh " effect and it certainly does this in spades! Without the rear element it is a 9" f4 lens approx and I have used it on both a Speed Graphic and a MPP Micropress.
When I read that the Dallmeyer Archive was now open I thought this an ideal opportunity to finally nail this lens once and for all as lenses are listed by type and serial number. However the results of the search have caused me much confusion. See the link:

http://www.thedallmeyerarchive.com/R.../Sliding/5.pdf

The lens is at the top of the left hand page and is listed as a No. 5 Triple Achromat in a rigid mount. Date is 1864 and serial number 8703. Made by a Mr Cole for customer A Dillan (?)
Having checked pictures of triple achromats this lens bears less resemblance than it does to the Portrait lenses so I am in conflict with a clear historic record. The front cell seems to be composed of two cemented elements, the front being convex and the rear having a flat exposed outer surface. As this is common to the achromat it is of no help.
Also this is not a rigid lens; it is in a sliding mount on which all the identification details are engraved although the fine focus wheel is missing.
I have checked details in the Vade Mecum and I am still doubtful this lens was ever a triple achromat.

So I have a bit of a conundrum. Does anyone have an example of a Dallmeyer triple achromat to compare this to? Or an Ordinary Portrait lens?
As 8703 is clearly engraved onto a sliding mount it is possible that the original entry was made on the wrong side of the page.