1. “Preliminary Report on the Use of an Improved Form of Electrocardiograph,” W. D. Reid, M. D. Jour. Lab. and Clinical Medicine, in press.
2. This is not intended as a general criticism of the string galvanometer. Like any other instrument, it can only be applied with due regard for its limitations.
3. This analysis was performed on a Coradi analyzer. The original record was carefully measured and replotted to a large scale (length of fundamental period = 40 cm; maximum ordinate 20 cm).
4. During recent years at least three electrocardiograph equipments using vacuum tube amplifiers have appeared upon the market. These produce records similar in appearance to those made by Einthoven string galvanometers. They undoubtedly possess some of the advantages of the equipment under discussion, but as far as the authors are aware no attempt is made to improve upon the conventional type of record.