This section is from the book "Cyclopedia Of Architecture, Carpentry, And Building", by James C. et al. Also available from Amazon: Cyclopedia Of Architecture, Carpentry And Building.
Fig. 164 illustrates an adjustable clamp for holding forms together. It is commonly used to hold the plank forming the sides of a beam or girder in place; it is used also in clamping the opposite sides of columns. It is forged from a 1 1/4 inch by 3/8-inch steel bar, and is held in place by the slotted forging, 1 inch square, by driving it tight.
Fig. 164. Adjustable Clamp.