I have an postcard, never written on or mailed, with a B & W photo of the Sheridan Troop, Tyrone, PA. Approximately forty to fifty men in dress uniforms are assembled on horseback, two of the horses are white, the rest are dark colored. They are assembled in what looks like a well-used baseball field. In the background is a low hill or levee with some large masonry buildings on or behind it. There is a tall chimney between the buildings. There are a number of people in the background including women in long dresses and hats. A parade? Mustering in? Mustering out? Anyone have an interest in this? Do you know what the event was?