36. Vernon Harcourt’s Percentage Chloroform Inhaler 115 37. Chloroform Mask 116 38. Chloroform Drop Bottles 117 39. Junker’s Chloroform Apparatus 119 40. Tube of Ethyl-Chloride 122 41. Ethyl-Chloride Inhaler 124 42. Guy’s Gas and Ethyl-Chloride Inhaler 128 43. Details of Guy’s Inhaler 129 44. Diagram of Gas-Oxygen Method Introduced by Dr Guy and the Author 130 45. The Guy Ross Gas-Oxygen Instrument 131 46. Rendle’s Cone 135 47. Clover Inhaler adapted for the Ethyl Chloride-Ether Sequence 139 48. Two Photographs illustrating Sylvester’s Artificial Respiration 146–7 49. Sitting-up Posture for Operations upon the Head and Neck 159 50. O’Malley’s Posture for Intra-nasal Surgery 160 51. All-metal Syringe for Infiltration Anæsthesia 176 52. Infiltration of the Brachial Plexus 183 53. Needle and Syringe for Spinal Analgesia 194 54. Position of the Patient for Spinal Analgesia 196 INTRODUCTION. The securing of a safe anæsthesia during operations is more important than ever before, partly because of the mere number of operations, and partly because of the greater extent to which other operative risks--hæmorrhage, shock and infection--have been overcome. The risk from the anæsthetic is now so very small that the joint aim of the surgeon and anæsthetist to abolish it altogether is not far from being accomplished. The author of this volume has done a good deal to accomplish this end, and it is a matter of congratulation that he has now published an account of his methods, so that a larger circle may benefit from his teaching and his experience. The author very properly goes further and maintains that anæsthesia must not only be safe but must also be good; good anæsthesia is absolutely vital to good surgery. Only a generation back many surgeons professed to see no difference as to who gave the anæsthetic; at the present day no one willingly embarks upon a difficult operation without the aid of a skilled anæsthetist.