16.Early electrical workers used it as a coating to insulate coils, and molded it into stand-alone insulators by pressing together layers of shellac-impreg-nated paper.
18.Therefore we point out a new method of testing fragile material's strength of extension.That is to say we can measure the disk's strength of extension by pressing in its diametric.
19.A little bag like that used in finger pressing is applied, with fifteen aromatic plants including wheat, cinnamon, yellow ginger powder, monarda, lavender, lime peel and moss rose contained in it.