[Footnote 38: It has been pointed out that this terminology, which is due to a large extent to Landois, presupposes a certain theory of the origin of the secondary elevations. (Edgren: Cardiographische und sphygmographische Untersuchungen, Skandinavisches Archiv. f. Physiologie, vol. 1, p. 92, 1889.) It is not easy to change a terminology, and the Greek terms, some of which were used by and before Galen, are so indifferently connotative that they can be kept without inconvenience. If one were to be rigorous, one would change the name of the sphygmograph into palmograph, because this instrument does not serve exclusively for the registration of the abnormal pulse. It does seem, however, advisable to drop the terms recoil wave (Rückstosselevation, Landois), and "onde de rebondissement" (Marey), because they are taken from modern languages and directly suggest a certain theory with which they are intimately connected.] [Footnote 39: Recherches sur l'état de la circulation d'après les caractères du pouls, Journal de Physiologie de l'Homme, vol. 3, p. 249, 1860; and La circulation du sang, p. 264, 1863. "Le dicrotisme du pouls est un phénomène physiologique, on l'observe presque chez tous les sujets; seulement il n'est sensible au doigt que dans les cas où il est extrêmement prononcé." References for previous observations of the slow descent of the pulse curve are given by Landois, Die Lehre vom Arterienpuls, p. 36, 1872.] [Footnote 40: Burdon Sanderson: Handbook of the Sphygmograph, 1867.] [Footnote 41: Lorain: Études de médecine clinique; Le Pouls, 1870.] [Footnote 42: Ozanam: La circulation et le pouls, 1886.] [Footnote 43: Pfungen: Pulscurve der Arterien in Gad's Lexicon der medicinischen Propaedeutik, vol. 3, pp. 544-642, 1895.] [Footnote 44: Riegel: Ueber die Bedeutung der Pulsuntersuchung in Volkmann's Sammlung klinischer Vortraege, Nos. 144, 145, 1878.] [Footnote 45: Roy and Adami: Heartbeat and Pulsewave, The Practitioner, vol. 1, pp. 81-94, 161-177, 241-253, 347-361, 412-425, 1890.] [Footnote 46: Cf. Howell: American Text-book of Physiology, p. 436, 1897. Marey's first explanation of the dicrotic belongs to this type (Comptes Rendus, vol. 47, p. 826, 22 Nov., 1858.) He supposed that the dicrotic elevation was due to a wave reflected from the Iliacae communes. He was led to this theory by the erroneous observation of Beau, that abnormal dicrotism never occurs in the lower extremities. Marey's own observations refuted this theory, since they show that the dicrotic elevation is found also in the sphygmograms of the arteries of the leg. (Marey, La circulation du sang, p. 274, 1863.)]