Mageth

crap - Middle English crappe, chaff, from Old French crappe, from Medieval Latin crappa, perhaps of Germanic origin.

From here:

"the term "crap" was in use when Crapper was only 10 years old and listed in a "Slang Dict." two years before Crapper founded his plumbing company"

Note that "craps" in dice has a different etymology - Louisiana French, game of hazard, from English crabs, lowest throw in hazard...

Marcel

Beastmaster already mentioned 'Shit' deriving from the Indo-European word for SEPARATE.
From this common root words like 'shift', 'shed' (watershed) derive. In Dutch you can trace it back easily:

Schijt (shit)
Scheet (fart)
Scheiden (to separate)
Afscheiden (to excrete)
Scheiding (parture, divorce)

In Afrikaans these words are skyt, skeet, skei, afskei, skeiding.

Funny; 'skeet', or actually in plural 'skete', also means 'caprices, whims'. 'Hy is vol skete'; he's full of whims', or, to stay within the boundaries of the argument, 'he is full of shit'.

Regards, Marcel.

Amen-Moses

Guano (or bird/bat dung) was shipped in vast quantities in the 19th century and at least one family here in the UK got stinking rich on the trade.

Amen-Moses