Stamp Design Subject Errors.

Hello all

I have done the search couldn't find anything on this subject,

what do you call an error of design in the subject or design of a stamp. for example St Kitts Nevis Columbus issue has him looking through a telescope which is an error as Columbus was around in the 15th Century but the telescopes where only invented in the 16th century, USA Boston tea party issue had the moon stuck in the rigging.
I read somewhere its called a "Plot Error" but can find no other reference to it.

(sound a few people scurrying to check the Tea Party stamps)HeeHee



If anyone could shed light on this it would be greatly appreciated.

Thin crescent.

https://www.csmonitor.com/1993/1110/10132.html

Design error. aka. blunder.

Boston Massacre by Paul Revere design error. Time on clock and position of moon.

https://graphicarts.princeton.edu/2...-time-wrong/

If you are interested in design errors on stamps, this site has heaps of them:

http://www.edbmb.net/stamps/

Thank you all for the wealth of information, this community never ceases to amaze me with
the help and relevant information,

Thanks again.

Ray

It sure does look to me like the hand at left must have a total of SEVEN fingers.