In 1957 the first author, as part of a development program to improve the liquid limit apparatus, approached the civil engineering faculties of Cornell University and Manhattan College independently (and unknown to each other) for assistance to study on a quantitative basis, the variations introduced in the liquid limit test resulting from modifications of equipment and variations in the procedures now used. It is known that in the extreme of variables the liquid limit on the same sample can vary as much as 30 per cent. This program sought to find and hold constant some practical combination of these variables to secure some standardization of procedure and insure repetitive results. It was also desired to find this combination from existing commercially available equipment without creating any new parts. Each college was given brand new sets of ASTM and Casagrande liquid limit test machines, grooving tools, and soil samples. They were instructed to use the ASTM Standard Method for Dry Preparation of Soil Samples for Grain-Size Analysis and Determination of Soil Constants (D 421-58) and the ASTM Tentative Method of Test for Liquid Limit of Soils (D 423-54 T) with some stipulated variations.