Epoxy resin sections form strong, heat resistant ribbons if, prior to sectioning, contact cement has been painted onto the leading and trailing faces of the block. The forming ribbon floats onto a drop of water held in place by a wax line drawn across the back of the glass knife parallel to the cutting edge. A long trough made from stainless steel tubing is inserted horizontally into the drop, and as the ribbon lengthens it is directed into the trough. The ribbon can be carried in the trough to a hot plate for expansion and then poured onto a slide for mounting. The serial ribbons obtainable by this simple procedure greatly facilitate three dimensional reconstruction of fine tissue structures.