Black and white drawing of a kangaroo standing on a rock surrounded by…

Diagram of a sphere with lines radiating outwards from the center

Black and white drawing of a brick wall with a clock on it

Black and white drawing of a floral design on a white background

Painting of a sailboat in the ocean at sunset

Black and white drawing of a pendulum on a white background

Man wearing a crown and holding a sword in one hand and a dragon in…

Old map of the city of Cologne

Black and white drawing of a city with mountains in the background