The desirability of automatically recording blood pressure in clinic routine has long been recognized, and with the advent of the new Tycos recording sphygmomanometer this seems at last to have become entirely practicable.
This latest development in the mechanical determination of blood pressure enables one to do away entirely with the stethoscope, palpating finger and indicating hand, thus eliminating completely the personal equation, and further gives a permanent record of unquestioned accuracy. Its service to the anesthetist, surgeon, diagnostician and general practitioner is well nigh incalculable, as it is also to the specialist in insurance medicine.
The instrument consists of a rigid reservoir of very light metal into which is set an air-tight collapsible chamber, also of metal, which expands and contracts with the pressure communicated to it from the rubber cuff encircling the arm. Attached to the upper member of this chamber is a bell crank assembly which gives a circular motion to