Dr. Horenstein's talk was illustrated by fascinating slides, both historic and contemporary. One showed us present-day Amsterdam Avenue, dipping down into what was once The Hollow Way, where much of the battle of Harlem Heights took place.
Another slide from the turn of the century revealed how much of the battlefield was still unspoiled at that time, down to the old stone fences. Dr. Horenstein explained the wisdom of building Forts Washington and Lee -- where the Hudson was the narrowest -- and why the patriots thought Fort Washington was impregnable -- it was the highest point in Manhattan.
We learned that Manhattan sits on three kinds of rock: gneiss, schist and marble, and chuckled at a geological joke: the Bronx is gneiss but Manhattan is schist. We were startled to learn how much of Manhattan was hilly in 1776. The numerous humps and bumps left by the glacier made a fighting defense seem reasonable to the patriots.
Most of these extrusions have been demolished by the real estate developers.
Offbeat, informative, fascinating were among the adjectives heard on the stairs as another well-fed troop of Round Tablers headed home.