Lithuanian to English Tech/Engineering Architecture 19th century

The one in question (in Antaviliai) appears to be a solid brick-walled pit (three bricks high) abutting the manor house's brick wall. I see no signs of glazing but there might have been fires lit in it as some of the brick are a little blackened and the bricks on the house wall have shed their outer skin, leaving them red to the grey of most of the rest of the brick. The bottom has a concrete (?) lip around the inside at ground level but the central part is missing like it had been busted out. It is possible the concrete was on a layer of brick or it could just be thick. No attempt was made to excavate further although the excavation continued down to sterile (natural) soil outside the 'pit'. There is no mention of a basement, although being a manor house, one is possible. There are no signs of any opening in the manor wall and the concrete lip is on that side as well. Any suggestions aside from the literal 'light pit', which, although possible, does not seem to be very common, even appearing in quotation marks in one place, would be welcome. A light well is like a large sky light, so also does not seem to be a fruitful avenue. While it looks like a barbecue pit in size and shape, judging from the name and location, I doubt it was used as one.