Mass. General Hospital and Harvard Medical School, 1853 (BPL Flickr Group).
West End, 1855.
This entry is built more upon the featured photograph than the institutions shown above, so it will not be one of my typical capsule histories. The image shows MGH (left) and the Harvard Medical School (the square building) on the edge of the Charles river, before the filling of the banks extended the West End into the waters. Notice that both buildings are sitting on pilings. At the time, and for many more years, the Charles was still a tidal river, and here we see it at a relatively low tide. It was not until the dam was built across the mouth of the river that ebb and flow of the river would be stopped up, and the lake-like basin we know now created.
So this photograph reminds us that the Charles river basin of our time - including the Esplanade - is an artificial creation - a prime example of man mucking about with nature. That placid puddle we see now was once a wild estuary, draining three river systems; the Charles, small Stony brook, and and still-smaller Muddy river. The building-out of Boston - and Roxbury - was at the expense of a broad, shallow estuary system of salt marsh and winding channels. The damming of the Charles created a tub of water for our viewing pleasure - and to save our sensitive noses from the stink of the mudflats.
As a bonus, I'll mention that four years before this photograph was taken, George Parkman's body was dismembered and disposed of within the Medical School building. The story of perhaps Boston's most notorious murder was doubly notable, considering that Parkman had donated the land for the school that was the scene of the grizzly deed. If you don't know the story, definitely investigate it - it's a classic Victorian horror.