Actual determination of center-of-buoyancy in Nautilus.

抄録

A new experimental method is presented in obtaining the center-of-buoyancy of Nautilus, and its physical reasoning is explained. Before experiment a model of Nautilus of uniform density is prepared, the shape of which copied exactly the lateral halves. The experiment starts with finding its balance-line with to explore on the flat plane corresponding to the animal symmetry. After the placement of the model on two isolated sticks, these were slowly brought close to each other. Ultimately these adjoin at the balance-line. Finding additional two balance-lines on the same plane will result in an intersection point, which corresponds to the center-of-gravity of the model. The intersection corresponds to the center-of-buoyancy of Nautilus. The validity of the present method is confirmed using another model, the center-of-buoyancy of which is able to explore theoretically.