Every Israel collector has once made an attempt to understand the different Running Stag watermark positions. The introductory paragraphs to the excellent Israel Handbuch issued by the ArGe Israel , on pages 304.1-2 give a good description of the watermarks Israel and Running Stag, as seen from the face of the stamp. As long as you bear that it mind the problem should be non-existent. Unfortunately when examining individual stamps it is usually easier to view the paper from the unprinted side rather than from the face. Upwards facing left should be interpreted as upwards facing right. But how about sideways watermarks??
In the explanation of how the 8 different positions of the Stag came to being the fact that paper can be gummed on the wrong side was made responsible by the ArGe for 4 out of the 8 positions. At least the way I read it.
Also P. Kanner  was quoted in writing that paper with gum on the wrong side was used for photo-litho printing, and paper with gum on the right side for photogravure.
Being an ardent student of stamp-printing methods and paper-making, having struggled with the Stag watermarks both statements struck me as not quite accurate.
After having read the article by H.H. Hirst  to which P. Kanner is referring, and the following reactions by M. Hesky [4, 5] and H.H. Hirst again , I thought it useful to set a few remarks of my own.
Unfortunately the results of my research will not solve the problem of easily determining the Watermark type/position. On the contrary, it may shatter you that I arrive upon no less than [in theory] 32 Stag-types instead of 8.
It will also be clear that some explanations given in the past [1955-1957] were completely wrong.
What I did was involving the phenomenon of the wire-markings a hitherto not well known aspect of stamp-paper research.