As you did me the honour, on a former occasion, to publish some remarks in defence of _auscultation_, against its enemies and detractors, I trust you will permit me to say a few words in reference to a communication in a late number, from a gentleman who appears to be a friend of that method of diagnosis, but whose ignorance of the subject is likely to be more injurious to the cause than either open enmity or secret detraction. The case in question (page 780, vol. ii.) appears, from the dissection, to have been clearly _emphysema of the lungs_, as there stated; but I appeal to every one practically acquainted with the physical signs of diseases of the lungs, whether the results of the exploration with the stethoscope, as narrated in the case, were those pathognomonic of that disease? I say they were not only not pathognomonic of this affection, but they were actually incompatible with its existence. The same ignorance of the subject is shewn in relation to the disease of the heart, which, I boldly maintain, no one was justified in pronouncing to be _hypertrophy of the left ventricle_ from the stethoscopic indications stated in the case. It is just possible that the writer of the case may have made further explorations on which his diagnosis was founded; but if he had such in his case-book, it is equally unfortunate for the credit of the stethoscope and his own, that he suppressed them in his printed case. I have the honour to be, Gentlemen, Your obedient servant, A STETHOSCOPER. Nov. 25, 1828. MECHANISM OF VOMITING. _To the Editor of the London Medical Gazette._ Glasgow University, Nov. 26, 1828. SIR,