First Bureau Issue Design Size Differences?

I recently was looking at some of my first bureau stamps (new color issue 1897-1903) and noticed that some of them appeared to have different heights. Below is a scan comparing the 15c to the 1c and 2c. I tried to align the bottom as best I could ... it looks as thought the design of the 1c and 2c are taller than the 15c. Is this because of the plate layouts (400 vs. 200)? Paper? I couldn't find any reference to design height differences in any of my references (Scott, Brookman, or Fragipane). Any ideas?

If there were differences, I assume the perforator settings would need to be different.

The 1 cent and 2 cent stamps pictured were produced from 400-subject plates; the 15 cent stamp pictured was produced from 200-subject plates. That implies that the already watermarked paper was fed into the presses in different orientation on the production of the 15 cent stamp than it was on the production of the other two stamps. This could cause design size differences between the 15 cent stamp and the other two stamps.

Since they were all wet printed stamps, this would be due to the direction of the wove paper grain. For vertical wove paper grain, the stamp would be horizontally narrower and vertically longer. For horizontal wove paper grain, the stamp would be horizontally wider and vertically shorter. See below:

The illustration above shows two booklet pane stamps printed by the wet method. The stamp on the left is shorter ("squat") because it shrank across the grain of horizontally wove paper, whereas the stamp on the right is narrower because it shrank across the grain of vertically wove paper. https://bnaps.org/ore/VanSomeren-Ad...ps-Paper.htm

Rhett and Jogil - thanks for those insights. Yes, as you both point out in different ways, the wove paper orientation would be different for these. The 1c, 2c were plates of 400 while the 15c were printed in plates of 200. Scott mentions that the 400 subject plates have horizontal watermarks while 200 subject plates have vertical watermarks. So, orientation of the wove paper grain would be opposite thus production shrinkage different.

Learning something new everyday!

And (being shorter) the image on your 15 cent stamp should be slightly wider than on the 1 and 2 cent stamps.

Here is an interesting and related SCF discussion: http://goscf.com/t/68080