Lysaght ORB Galvanized Tinned Sheets

Sheets with the reversed or mirrored trademark

The claim that they are seconds

Spennermann in his analysis of another building where sheets were found with marks mirrored asserts this is not from stacking while wet, because there is no smudging, so he then assumes it was an intentional way of marking "seconds", or faulty sheets, which were sold at a lower price. This needs much more elaboration which is not provided in the report.

Having my own examples and need to know, I need to dispute this with the following analysis.

Evidence of secondary transfer

It is clear from image 1 below (from the roof of this schoolhouse) that it is a secondary transfer because only the outlines of the stamped primary have been transferred. And they are clearly smudged either through movement of one sheet relative to the other or the ink has spread/bled as the sheets have been pressed together as the weight of the stack increased. I am not sure at what stage the sheets are marked but assume it is prior to corrugating, i.e. while the sheets are flat.

1. Lysaght ORB Galvanized Tinned roof sheets.

This is not a reversed photo.

Note the smudging at the bottom and outlining, indicating that this is a secondary transfer off a partially dry positive.

For comparison, images of positive prints:

The outlines are thicker and therefore take longer to dry because excess ink is squeezed out from between the raised areas of the stamp and the sheet, to accumulate at the edges of the raised areas (the outlines). To corroborate this to some extent, images of positive transfers show areas where the outlines are darker than the interiors. This of course is dependent on the control of the amount of ink deposited on the stamp. A well controlled application of ink that doesn't produce excess at the edges need not produce secondary transfers, as evidenced by the fact that the interior areas have dried sufficiently before stacking that they are missing in the reverse image.

More questions

Other questions that need to be answered:

  • Were factory seconds imported at all? Production and shipping costs would be the same for seconds as for firsts so it would make sense to export the product with the highest margin to start with. It would be more profitable to sell the seconds in Britain. There was also a documented period during which Lysaght were making a small loss on exported sheets and so exporting the higher margin product would minimise the loss.
  • Would the mill really use a reverse print to denote seconds? From about the 1960s we know Lysaght positively marked sheets as "seconds". I don't know if they also included the brand trademark on those sheets, the Lysaght Referee is not explicit on that.
  • If deliberate, how was this reverse image achieved? It's clearly a secondary transfer as demonstrated.
  • Deliberately printing reverse images on sheets would necessitate ensuring that similar images never occurred accidently. There is no advantage at all to be gained by marking seconds this way.
  • Why do we see this only on sheets with this trademark? How were, for example, the QUEENS HEAD flat sheet seconds marked? Any recorded examples?


The premise that there must be smudging to indicate secondary transfer by stacking is unsubstantiated in the Spennermann report.

The handling would be designed to minimise this because to smudge the negative is to smudge the positive.

Nevertheless, there is evidence of smudging, even in the Spennermann report itself. The report's Fig 58 shows a reverse image that is very clearly smudged and displays the same outlining as image 1 above, which is indicative of secondary transfer. Figs 231 and 232 of the report are two images of the same mark and clearly show a partial imprint or smudge to the right of the orb symbol that isn't part of the mark - possibly an initial contact before the sheet came to it's settled position. And then there is my image 1, which also shows smudging.

Impossible to prove either way

If image 1 does show a secondary transfer from the sheet above in the stack then logically there would be a positive image on the other side of each sheet, but proving that is almost impossible. Any sheets left unpainted would have lost the exposed positive long ago and if painted have been buried. I'm not about to attempt to peel a sheet of paint off to find out, not yet. There is another possibility: in each stack there should be at least one sheet that does not have the reverse image, i.e. the top or bottom sheet. But once again, without an example of a single sheet with both positive and negative images it does not prove the point.


The contractor Samuel Cox was a well known member of this small community where reputation matters, was very keen for this schoolhouse to be a show case in gaining further work. His audience, many of whom had built structures on their own properties using corrugated iron, would easily have identified seconds during the build if it had been used.

There was clearly no skimping in any other area of the building and no reason to skimp on the roof sheeting.

Proof in the longevity

For sheets that are supposed, not by me, to be seconds they have lasted a very long time, with some years or decades still before they will need to be replaced.

I argue that they are from the original 1879 build, which would make them 140 years old now. They will, with reasonable maintenance, last several more decades.