Reprint of two papers entitled 'Isotherms of CO2 between 0O and 150O and Pressures from 16 to 250 ATM (AMAGAT Densities 18-206)' and 'Isotherms of CO2 between 70 and 3000 Atmospheres (AMAGAT Densities between 200 and 600) Reprint of two papers entitled 'Isotherms of CO2 between 0O and 150O and Pressures from 16 to 250 ATM (AMAGAT Densities 18-206)' and 'Isotherms of CO2 between 70 and 3000 Atmospheres (AMAGAT Densities between 200 and 600)