Correspondence MCA, With regard to actual technique, the regimen for a postpartum tubal ligation, for example, would be: methadone 10 mg., promethazine 25 mg. given intramuscularly half to one hour preoperatively,; and, intravenously, methohexitone I mg./kg. body weight, given slowly, followed by 4-HB 40 mg./kg. for induction of 4-HB narcosis. The patient's head is then turned to one side. A Guedel airway is gently inserted in most cases. The surgeon normally requires to use 20 ml. of 0.25%

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... ocaine with 1 in 200,000 adrenaline to achieve entry to the peritoneal cavity. Without local anaesthesia twitching movements of the limbs wourd occur if an incision was made into an unanaesthetized area. Consciousness occurs a half to one hour after induction. For prolonged surgery I presently recommend a quarter the induction dose of 4-HB at half-hourly intervals. Under 4-HB narcosis the response to a strong stimulus outside the field of local anaesthesia can be conveniently anticipated and dampened by 10 to 20 mg. methohexitone given intravenously, without airway or respiratory problems ensuing. The optimal induction dose of 4-HB for children is 50 to 60 mg./kg. body weight. Surgery under 4-HB narcosis combined with local infiltration anaesthesia does not require intubation, the use of relaxant drugs, or an anaesthetic machine. As experience is gained with 4-HB further indications for its use will evolve. This drug does not fit into existing patterns of anaesthetic thought. New concepts must be built around it. A short review of the drug is given by Robertson. '-I am, etc., M. E. TUNSTALL.