I gave my respects to the Bakalises after I saw this fine monument to them in Green-Wood Cemetery in Brooklyn. Installed on a small hill, its solar cells on the two short sides are what attracted my attention on a recent walk.
My guess is that the cells charge batteries during the day, which in turn power a light from within the cross cut into the headstone at night. As this is a fair walk away from where I live, I haven’t seen it from 5th Avenue in the dark (the cemetery is closed at night).
While there are larger memorials and mausoleums in the cemetery, I have a lot of respect for the thought and engineering that went into creating this one for the Bakalises.
Dynamic Subspace 