An addendum to Merchant's (2001) etymology of "Sluicing"

Syntacticians will recognize the term as referring to elliptical constructions like (1):

(1) Ross (1969) named this construction sluicing for some reason, but I don't know for what reason Ross named it sluicing.

Merchant (1999, 2001) writes, "Ross has always been known for his onomastic fecundity, though this particular example is less transparent than many of his other christenings. It presumably picks up on the sense of the verb sluice (Webster's 2nd gives the following etymology: from the Dutch sluys, sluis < OFr escluse < LLat exclusa, the past participle of Lat excludere 'exclude, shut out') meaning 'to wash off with a rush of water', metaphorically extended to the 'washing away' of the sentence below the wh-phrase. A more fanciful interpretation would trace the origin of the term to the approximate sound-similarity of sluicing to "SIosing", in the sense of "losing" the S node under the wh-phrase (cf. S-Iifting 'slifting' and wh-is 'whiz' deletion)."

Merchant is right about the metaphor of washing off; I wanted to write down somewhere, for posterity's sake, Howard Lasnik's (p.c.) report that there is something even more particular and whimsical to the metaphor. According to Howard, Ross was thinking particularly of panning for gold using a sluice box. Not only is the sentence washed away, as Merchant says, but there is also a bit of gold residue left behind afterwards; the remnant wh-phrase.