I dunno .........
..................... I've seen marital become very similar to martial ...........
.......................................... almost experienced it .
I had one but it rolled right over ......
I now use a weather string .... much the same as the rock but also includes air movement indication ...
.. string moving = breeze
.. string horizontal = stronger wind
.. string missing = batten down the hatches; OR thief in local area
A few years ago I recall hearing that a whole Chinese weather bureau got to spend time in tha callaboose for getting their forecasts rather wrong.
Something about monsoons and flooding or some such .....
I used mine at our Nationals one year ..... lobbin' spent hulls into tha peanut gallery ...... on about the 9th stage of the event I finished shooting and the TO and I were showered with spent hulls FROM the peanut gallery ........ HUGE GRINS all round
(I considered it a great compliment )
wbj