[aruanan]

The only source I know about for those measurements is Miskowski (sp?) it is generally agreed that his measurements were not indicative of the global CO2 but represent mostly elevated CO2 around cities.

Throughout the 19th century there were many thousands of CO2 measurements taken around the world.

[palmer]

Beck has documented those measurements in a presentation: http://www.wasserplanet.becsoft.de/CO2-Dateien/Summary-bayreuth-e.pdf and paper http://multi-science.metapress.com/content/q46551865h237235/

But read the comment here: http://cio.eldoc.ub.rug.nl/FILES/root/2007/EnergyEnvironMeijer/2007EnergyEnvironMeijer.pdf to see some of the flaws in the Beck paper. AFAIK, Beck has not written a new paper since then.