A 200 year old brain coral, captured in Bermuda in 1976 was slabbed and x-rayed. Using the annual growth bands sequential, dated samples were taken over the entire growth period of the coral and analyzed for Δ14C, &sgr;13C and Δ18O. During the past 80 years atmospheric variations in Δ14C and Δ13C due to human effects, such as release of bomb C-14 and dilution of both C-14 and C-13 by fossil fuel burning, are closely tracked by the coral. Prior to 1900 divergences between the coral and tree Δ14C and Δ13C can be related to world-wide changes in plant production and possibly oceanic upwelling rates.