CHAP. V.
WATT FINDS THAT CONDENSATION IN THE CYLINDER IS INCOMPATIBLE WITH A DUE ECONOMY OF FUEL.—CONCEIVES THE NOTION OF CONDENSING OUT OF THE CYLINDER.—DISCOVERS SEPARATE CONDENSATION.—INVENTS THE AIR-PUMP.—SUBSTITUTES STEAM PRESSURE FOR ATMOSPHERIC PRESSURE.—INVENTS THE STEAM CASE, OR JACKET.—HIS FIRST EXPERIMENTS TO REALISE THESE INVENTIONS.—HIS EXPERIMENTAL APPARATUS.—DIFFICULTIES OF BRINGING THE IMPROVED ENGINES INTO USE.—WATT PRACTISES AS A CIVIL ENGINEER.—HIS PARTNERSHIP WITH ROEBUCK.—HIS FIRST PATENT.—DESCRIPTION OF HIS SINGLE-ACTING STEAM ENGINE.
