That beautiful girder-to-column connection is in an 1870s warehouse in the Bronx. The basics of it are quite simple: the two spans of girder are connected with a scarf joint, and sit on a cast-iron shoe that caps the column below.
First off, there’s an interesting contrast here between the pre-fab, bulk-manufactured iron shoe and the wood joint, which required a bit of skill on the part of the joiner. The story of changes in construction technology in the US is very much one of replacing labor on site, whenever possible, with cheaper labor in factories; and replacing skilled labor, whenever possible, with unskilled or semiskilled labor. Skilled iron workers might be as expensive to hire or more than skilled carpenters, but their output using industrial methods was far greater, and the shoes replaced a lot of complex wood connections at a far lower cost.
Second, minor alterations can cause trouble. Wood is far weaker in shear along the grain than across it, so shear overloads manifest as longitudinal cracks, The scarf connection acts to concentrate shear stresses, which shouldn’t be a problem since both girders (left and right of the column) are bearing on the shoe. But someone drilled a hole right through the area of greatest shear to let that black pipe pass through the wood. Maybe they drilled through a check (a natural split in the wood) by coincidence, maybe they caused a split by drilling the hole. Either way, it’s a bad look.
Finally, note that the shoe is a little loose-fitting around the column. It might seem like that’s a bad idea and the connection would be stronger if the wood fit exactly within the iron socket. But…on at least one occasion, a building collapse was attributed to rot in the columns that started in a tightly-fit shoe. Rot fungi don’t like oxygen, and so the loose fit helps keep them from attacking the wood.
