“PREPARATION OF DICHLORETHYLSULFIDE—The thiodiglycol was taken from the rail to two large storage tanks and thence drawn by vacuum direct to the reaction vessel. Each reaction vessel was placed in a separate cubicle ventilated both from above and below and fitted with glass windows for inspection. The vessels themselves were made of 1¼ in. cast iron and lined with 10 mm. lead. They were 2.5 m. high and 2.8 m. in diameter. These tanks were jacketed so that they could be heated by water and steam, and the reaction was carried out at 50°. The hydrochloric acid coming from the main pipe was passed through sulfuric acid so that the rate could be observed, and passed in by means of 12 glass tubes of about 2 cm. diameter. The rate of flow was maintained at as high a rate as possible to procure absorption. The vapors from the reaction were led from the vessel through a pipe into a collecting room, and then through a scrubber containing charcoal and water, through a separator, and then, finally, into the chimney. These exhaust gases were drawn off by means of a fan which was also connected with the lower part of the chamber in which the reaction vessels were set, so that all the gases had to pass through the scrubber before going to the chimney. When the reaction was completed, the oil was removed by means of a vacuum, induced by a water pump, into a cast iron washing vessel. “The hydrochloric acid layer was removed to a stoneware receiver, also by vacuum. A glass enabled the operator to avoid drawing oil over with the acid. The pan was fitted with a thermometer to the interior as well as to the jacket. For testing the material during reaction, provision was made for drawing some up by vacuum to a hydrometer contained in a glass funnel. The final test at this point read 126° Tw. Another portion could be drawn up to a test glass and hydrochloric acid passed through it in full view. A float contained in a glass outer tube served to show the level of the liquid in the vessel. The pans in which the operation is carried on, as well as those employed for washing and distilling the product, were of a standard pattern employed in many other operations in the works.