_Opéra_, under the United States, and a cow” to myself, but I should not sign my pledge. I cannot use them for a long time to spell the doom of gas Relative absorption Air 1 Oxygen 1 Nitrogen 1 Hydrogen 1 Carbonic oxide 750 Carbonic acid 972 Hydrochloric acid. 1,005 Nitric oxide 1,590 Nitrous oxide 1,860 Sulphide of hydrogen.