The ship's bodily sinkage caused by her passage through the restricted channel was the most important primary effective element to decide how much to need the bottom clearance for the safe navigotion of very large vessels. As the results of the tank test of ship's model (1m, 2m, & 3m in length.), we observed the following facts ; a) In the general type of very large vessels with a bulbous bow, the sinkage of bow was more than that of stern, and even if the depth of water becomes extremely shallow, excessive sinkage of the stern, what was called, SQUAT, did not occur. b) The initial trim had not so much effect on the mean sinkage, but only on change of trim underway. c) Though tendency of trim of the bow could be applied to very large vessels, it was done not always to other ships. d) Revolution of the model's propeller had not so much effect on the bodily sinkage. e) The bodily sinkage, tested at every various speeds in the restricted water, generally indicated the same tendency as values calculated by J. Kreitner's method.
