You might be able to rig up something from a BBQ propoane tank gauge. I
would suspect that RV's use this sort of thing and also that Joel will
have an answer for us tomorrow morning. 

BTW the advantage of the strip thing is cost and I suppose installation.
Warm breath unfortunately is not enough to activate it, but I suppose if you
are camping and can enlist the aid of gynecally-challanged mate and
encourage him at the right moment (preferably early morning while its still
foggy) to utilise his functionally operative fluid dispensation device on
said tank this would also give an accurate reading. This assumes also that
your aim is not too good and that you can tolerate this sort of thing,
never tried it wouldn't know....DC

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David Carment
School of International Affairs
Carleton University
Ottawa, Ontario
K1S 5B6
voice - (613) 788-2600-6662
fax - (613) 788-2889
Email address: dcarment@ccs.carleton.ca
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