抄録
The writer has serially presented the difference solution for each group of rectangular plates shown in the title. Tests are made in order to check the propriety of the assumptions on which his method is based and also the accuracy of the numerical results. In spite of the practical existence of various ferroconcrete works with slits or square openings fiew investigations have been made on the bending of slitted slabs except by P.S. Symond or Nomachi and of the slabs with square openings except by Wiedemann, Gyoten or Furr who gave approximate solutions to some cases of square slabs with concentric square openings by the method of finite difference or others. The writer's difference expressions round the opening are different from Gyoten's or Wiedemann's in their derivation from the boundary conditions. The fact of our having no strict analytical access to these slabs for the present requires any experimental measure of the accuracy of our solution.
