A new method of tissue culture for accurate and rapid measurements of the growth

The new method of culture consists in placing the tissue in capillary tubes instead of hanging drop, which was employed heretofore. The glass tube consists of two parts: one part, about 1 mm. in diameter, is used for handling by the operator, the other part, drawn out to about 0.3 mm. in diameter, is filled with the liquid medium, into which is placed the tissue to be cultivated. The thickness of the walls of this second part of the tube is less than 0.1 mm. The length of the whole tube is about 2 inches. 20 such tubes are placed with the thin ends down into a small beaker. A few drops of fluid are poured into the beaker, and this fluid through capillarity fills the tubes. The whole is placed into a test tube and may be sterilized and cooled without handling the individual tubes. A piece of tissue about 0.5 mm. in its widest diameter is placed into the wide part of each tube and then by the aid of a very fine glass rod immersed into the fluid, then with a piece of dry cotton attached to the thin end of the tube a drop of the fluid withdrawn and at the same time the tissue moved deeper in the fluid. The tissue becomes elongated and grows only at both ends and consequently in one direction. It is therefore quite easy to measure the longitudinal increase in size with accuracy of nearly 1/20 of a millimeter. The narrow end of each tube is closed with sealing wax and the thick end by a gas flame. As a result of this manner of sealing the tube the piece of tissue falls out without effort on breaking off of the thin end of the tube.