In message , GB
writes
geoff wrote:

As there is much less carbon in gas,

Would you like to expand on that ?

Natural gas is mostly methane, ie CH4. My recollection is that the older
town gas used to include some longer chain hydrocarbons (which have a lower
carbon/hydrogen ratio than methane) as well as a fair amount of CO, which of
course has no hydrogen at all.



I think we all know that

I was trying to get at what harry thought was the relevance when it came
to using a co / co2 meter


--
geoff