The solution of common salt—from 1 to 5 per cent—in distilled and sterilized water, is employed for this purpose. A fountain syringe with a suitable needle for transfixing the skin is the simple instrumental means required. The hypodermatic needle is suitable for most of the cases, but longer and larger needles may be necessary in special cases. The best places for practicing the infusion are those where the skin is loose and the space most abundant, as in the armpits, in the lumbar and inguinal, and in the popliteal regions. The pressure obtained by elevating the reservoir determines the rapidity with which the solution enters the subcutaneous connective tissue. The effect of the infusion on the powers of life is remarkable. In fact, it has been found that the method of infusion of salt solution is nearly equal to the intravenous injection of the same, or to transfusion of blood. This procedure has greatly developed in the last few years, and is freely used in conditions of depression of the powers of life, the result of haemorrhage or exhausting discharges, in uraemic convulsions, in diabetic coma, and in many cases in which heart failure is threatened by sudden losses of fluid, or by unexpected weakness of the centers presiding over important functions.