Charged and evacuated depolymerization apparatus were prepared as above in batches of six at a time. The batch of apparatus was grouped with the stills together, so that they could be heated in a small Woods' metal-bath. The connecting tubes radiated outwards, and the lower p: ?s of the condensers were cooled in Dewar Hasks containing Drikold "-methanol mixtures at -70'. When this arrangement of apparatus was ready, the metal-bath heated to 250Β° was raised from below the stills so as to immerse the latter to a depth of about 4 cm. Timing was started at this point. Heating was applied for IOO minutes with the bath temperature hand regulated to 250". At the end of this period the bath was lowered and the stills and condensers separated by drawing down the connecting tubes at E.
Each condenser was weighed and opened at E by marking the side tube with a glass knife and breaking off the tube.
Distillate was emptied out and its refractive index measured. The condenser was washed out with methanol, chloroform, and ether and dried at 100' before re\veighing with the rest of the tube E. Weight of distillate was obtained by difference of the two results, correction being made for the weight of air to fill the evacuated condenser.