The first mixture introduced was known as ACE, and consisted of one part absolute alcohol, two parts chloroform, and three parts ether. Alcohol evaporates very slowly and if it be introduced at all it should be in much smaller proportion. Schäfer’s mixture is one part alcohol to nine parts chloroform. Neither of these mixtures is now much used. The most useful combination is two parts chloroform and three parts ether, and is known as C_{2}E_{3}. In special cases, one part of chloroform to two parts ether may be better. Methods. _Cones_ of varying type were at first extensively used for mixtures. The best known is Rendle’s (Fig. 46). It is made of celluloid, and is perforated at the top by a series of small holes through which the anæsthetic is introduced. A sponge is packed into the upper part of the cone, and a flannelette cover completes the appliance. The objection to the use of this and kindred cones is that since chloroform evaporates more slowly than ether, the more dangerous drug is apt to collect in the sponge, completely altering the strength of the vapour after a time. This fault is remedied to a large extent by the open drop method now used. [Illustration: FIG. 46.--Rendle’s Cone.] The Open (Drop) Method. For this the mask and ether dropper of Bellamy Gardner are admirably suited (Fig. 27). A material less close than the gauze advocated for open-ether is required. One layer of flannelette does very well, or the cheap cotton towels which used to be known in Edinburgh as “penny towels” in the pre-war period. The mask should fit the face with reasonable accuracy: there is no reason why a gauze ring should not be used to ensure this if the administrator is careful to adhere strictly to a “drop” method. The bottle into which the dropper is inserted should be of different _colour_ to those in which pure ether is habitually carried. This is a greater safeguard against a dangerous forgetfulness than a mere label. As already said, the anæsthetic must be given by a strict “drop” method. “Douching” at frequent intervals gives results far inferior. THE TYPE OF ANÆSTHESIA is a compromise between that of chloroform and open-ether. Respirations and colour are better than with pure chloroform, not so good as with open-ether. The size of the pupil is also intermediate. SCOPE.--As elsewhere explained there are many patients to whom open-ether cannot well be given; the greatest number of these can take a mixture perfectly and C.E. should certainly be chosen in preference to pure chloroform when possible. For refractory cases, it serves admirably as the inducing agent before the use of open-ether. CHAPTER XV. SEQUENCES.