Sentence:  Oak tables displayed platoons of typewriters: <WSD>downstrike</WSD> typewriters, upstrike typewriters, vintage World War I typewriters, turn-of-thecentury typewriters—a 1901 Armstrong, a Densmore 1, a brass 1881 Hamilton Automatic, even an 1877 Sholes & Glidden in its case --each perfect in its kind, primed and polished so the metal shone. 
Meaning of the word marked with <WSD> tags:  A type of manual typewriter that causes the letters to print on the downstroke of the keys and retract as the key rises.