An inequality may take place in respect to one pulsation; for the dilatation of the artery may be interrupted, and then completed, when it is called _dorcadissans_, _caprizans_ or _goat-leap_; or the stroke may be suddenly repeated, when it is called _dicrotos_, which may be translated the _double_, _reverberating_, or _rebounding_ pulse. The term _dorcadissans_ is derived from _dorcas_, an animal generally supposed to have been the goat, but it is now satisfactorily ascertained that it was the _antelope dorcas_ or _gazelle_; and, in the Latin translations of Avicenna and Haly Abbas, it is rendered _gazellans_. It is said that when this animal leaps upwards it at first takes a short spring, then seems to make a sudden stop, and afterwards takes a much larger and swifter bound. This character was applied to the pulse when an imperfect dilatation of the artery is succeeded by a fuller and a stronger one. (Galen, de diff. Puls. i, 28.) It is thus described by Haly Abbas: “Gazellans pulsus est qui cum a celeritate incipiat antequam percussiat stat, dehinc velociter movetur: vocatur autem hujusmodi gazelenus suâ ex similitudine caprioli saltu: quum capriolus quem Gazel Arabicè vocant cum saltum dederit pedes tollit et suspensus pauco videtur tempore atque sic ad terram velociùs redit.” The translator of Alsaharavius renders it by _fusalis_. It is correctly stated by Fouquet that the second pulsation is necessarily larger than the first. The _dicrotos_ consists of two pulsations, following upon one another so rapidly as to form, as it were, but one beat of the artery. In the translation of Alsaharavius it is called _mallearis_, and is thus defined: “Est autem pulsus mallearis qui percutit manum et recedit, deinde redit et percutit secundario.”