The employment of guncotton as a propellant was possible only after the discovery that it could be gelatinized or made into a colloid by the action of so called solvents, e.g.
The separation of organic substances by filtration under high pressure through a colloid membrane, gelatine supported in the pores of a porcelain filter being usually employed.
Trans., London, 1893); Notkin, " Nature of Colloid in Thyroid Gland," Arch.
Some solutions of nitroglycerin (in ether, acetone, &c.) burn quietly, and the same is the case when it is held in solution or suspension in a colloid substance, as gelatinized guncotton, &c.
These cells become swollen by this translucent substance and are thrown off into the space where they become fused together, forming colloid masses.
The wax-like or amyloid substance has a certain resemblance to the colloid, mucoid and hyaline.
If we assume that a certain minimum electric charge must be brought into contact with a group of colloid particles to produce coagulation, twice as many univalent ions must collect to produce the same effect as a number of divalent ions, and three times as many as an effective number of trivalent ions.