I ran across this today in a very old home (1873). It was a historical building that has been decently preserved. This five gallon bucket with a sealed lid had one “inlet” pipe from the sink drain, and one “outlet” pipe to the house drain. The house drain was DIRECTLY BELOW this setup, in the basement. I popped the lid, and there was no pump or anything in the bucket, so this isn’t some kind of improvised “lift station” pump to direct drainage to a higher elevation drain. Again, to be clear, all of the fixture drains on the main floor drain to the main drain in the basement below. IM not asking if this is a defect or not, I know that it is, Im just genuinely curious as the the why behind this? Home made grease trap possibly??
Good guess as any.
Video of a similar bucket trap
3 Likes
Looks like an interceptor of some type. If they made jewelry, it could be precious metals or gems. If they polished rocks, it could be for sand or grit.
3 Likes
Looks like a homemade attempt as a grease trap or separator.
3 Likes
wow never seen this but ok
New to me, thanks. Learning something new 
Looks like you found a clay trap - common to find in pottery studios to keep clay from clogging up the drains and out of the wastewater system. The bucket is to catch sediment, which you can clean out and sometimes reuse.
2 Likes
3 Likes
Looks like we have a ‘winner’. Now, seems like there should be a P-Trap down stream from this for sewer gas. 
?
I believe it remains full of water with sediment dropping to the bottom and clear flowing off the top. (septic tank theory).
2 Likes