The fourteenth meeting of the Graphite Expansion Committee was held on February 7, 1947. Laboratory studies indicate that either the graphite thermocouples are reading low or that annealing effects at elevated temperatures within the pile are much greater than those encountered In the laboratory. Current difficulties with operation of some of the horizontal and vertical control rods seem to be attributable to graphite expansion, though no complete understanding of the phenomena has been obtained and one is unable to predict the time required for similar difficulties to develop in other rods. Changes in clearance between process tubes and pile graphite in the D Pile have been erratic in nature but have averaged much less than had been anticipated. The negligible decrease in clearance for central tubes indicates that the expanding cross-wise graphite layers are slipping with respect to the graphite layers which contain process tubes.