Excerpt - page 1783: "... Chemical Designation Name Name Formula CH2CH2C1 H, HD Sulfur Bis-(2-Chloroethyl) sulfide S / mustard 2,2'-Dichloroethylsulfide \ CH2CH2C1 C1\ AsCH=CHC1 L Lewisite 2-Chlorovinyldichloroarsine Cl' ß-Chlorovinyldichloroarsine ..."
Excerpt - page 282: "... the Germans started heavy shelling of the Ypres positions with dichloroethyl- sulfide gas shells. The Germans called this new and deadly gas, ..."