This section is from the book "Complete Self-Instructing Library Of Practical Photography", by J. B. Schriever. Also available from Amazon: Complete Self-Instructing Library Of Practical Photography.
Center Of Plate Sharp, Ends Out Of Focus, Appearing Blurred. This clearly shows that the lens does not cover the entire plate or it was necessary to use the swing-back to an extreme. This difficulty can be overcome by using a small stop.
Objectionable Shadows On Buildings. To overcome this difficulty it is necessary to select a time of day when the buildings and trees on the opposite side of the street do not cast a shadow on the building which is being photographed.
Tripod Slipping On Polished Floors. When impossible to make the tripod legs hold to the floor you should lay a small piece of carpet or a rug down and stand the tripod on it. Small flat blocks of rubber may be employed for this purpose, or a triangular frame made of wood, the sides being not less than 30 inches long.