Cutting tests are useful for materials that do not lend themselves easily to standard toughness tests, because they are difficult to shape, take a high strain to fail, are viscoelastic or thwart an intended crack direction by deflecting it with irregularly placed structural obstacles [1]. However, cutting tests are incompletely understood. Ideally, such tests reduce the deformation of the specimen to a negligible level such that the energy input into the specimen is totally converted into fracture [2-4]. We were interested in developing a simple test that could register very small increments of work for use on biological materials. A sharp guillotine may produce negligible deformation of sufficiently thin sheets of material [3]. However, excess work is done against friction, due largely to contact between the blade and the base-plate. The estimation of R, the fracture energy, necessitates a subtraction of frictional work by making a second identical "empty pass" of the blade. "]['he drawback is that it is unverifiable whether the correct amount of work is subtracted. Most guillotines use high forces in the "empty pass", which restricts the sensitivity of the test for use with biological materials, so we experimented with scissors. A pair of tailoring scissors (A-220, Dragonfly, Korea), possessing accurately set and very sharp high-carbon steel blades clad by mild steel, was mounted in a Bakelite mould such that one handle of the scissors was supported firmly all along its length. It was then attached to the modified surface of a compression platen. The free handle was contacted by an upper platen in line with a load cell in a universal[ testing machine (DCS-5000, Shimadzu, Japan). Two sets of plastic blocks were built up on either side of the stationary blade, such that the specimen could be laid across them and kept in contact with the blade by weights placed on either end. The upper platen was. moved at 30 mmmin -I and the results were displayed on a force-t ime chart recorder (Dataletty 401, Shimadzu, Japan). Three passes of the blade were made: (1) fracturing the intact specimen, (2) with the fractured specimen still in place and (3) with the specimen removed. The integration of the areas under these curves, which gave the energy input for each pass, was performed automatically by the recorder. The length (l) of cut was measured with vernier calipers to 0.1 mm and the sheet thickness (t) with a micrometer to 0.01mm. A brief comparison was made with a guillotine (unbranded) which had a spring-loaded handle but which was otherwise operated as previously described in [3].