A treatise on the diseases of the chest and on mediate auscultation / by R.T.H Laennec ... ; translated from the latest French edition, with notes and a sketch of the author's life, by John Forbes ... ; with plates ; from the third revised London edition, with additional notes.

  • Laennec, R. T. H. (René Théophile Hyacinthe), 1781-1826.
Date:
1830
Catalogue details

Licence: Public Domain Mark

Credit: A treatise on the diseases of the chest and on mediate auscultation / by R.T.H Laennec ... ; translated from the latest French edition, with notes and a sketch of the author's life, by John Forbes ... ; with plates ; from the third revised London edition, with additional notes. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    shape by paste. The longitudinal aperture which is always lei* in the centre of the paper thus rolled, led accidentally in my hands, to an important discovery. This aperture is essential to the exploration of the voice. A cylinder without any aperture is best for the exploration of the heart: the same kind of instru- ment will indeed suffice for the respiration and rattle; but both these are more distinctly perceived by means of a cylinder which is perforated throughout, and excavated into somewhat of a fun- nel-shape, at one of its extremities, to the depth of an inch and a half. The most dense bodies do not, as might have been ex- pected from analogy, furnish the best materials for these instru- ments. Glass and metals, exclusively of their weight and the sensation of cold occasioned by their application in winter, con- vey the sounds less distinctly than bodies of inferior density. Upon making this observation, which at first surprised me, I wished to give a trial to materials of the least possible density, and, accordingly, caused to be constructed a cylinder of gold- beater's skin, inflated with air, and having the central aperture formed of pasteboard. This instrument I found to be inferior to all the others, as well from its communicating the sounds of the thoracic organs more imperfectly, as from its giving rise to for- eign sounds, from the contact of the hand,&c. Bodies of a moderate density, such as paper, the lighter kinds of wood or Indian cane, are those which I always found prefer- able to others. This result is perhaps in opposition to an axiom in physics ; it hasr nevertheless, appeared to me one which is in- variable. In consequence of these various experiments I now employ a cylinder of wood, an inch and a half in diameter and a foot long, perforated longitudinally by a bore three lines wide, and hollowed out into a funnel-shape, to the depth of an inch and a half at one of its extremities. It is divided into two portions. partly for the convenience of carriage, and partly to permit its being used of half the usual length. The instument in this form- that is, with the funnel-shaped extremity,—is used in exploring the respiration and rattle: when applied to the exploration of the heart and the voice, it is converted into a simple tube, with thick sides, by inserting into its excavated extremity a stopper or plu*r traversed by a small aperture, and accurately adjusted to the