The Difference Between Porter and Stout

With Ron wasting the summer writing about trivial subjects like lager and travel, little progress has been made recently in droning on about important matters. Those matters of course are porter and stout, and the difference between the two. So here is a quote from and industrial chemistry manual published in 1921.

"Stout, with a very dark color, malt flavor and sweet taste, brewed stronger than ale, and possessing a tart taste in the aged product, but less alcohol than ale; usually lively. From worts of about 16 to 18 per cent extract.

Porter, with a dark color, brewed like stout, but not so strong."

-"Industrial Chemistry: A Manual for the Student and Manufacturer.", page 921.