M. Hoffman has written to specially recommend this acid in haemoptysis; and the main reasons for his preference of it would seem to be its "less corrosive action," and better toleration by the stomach, otherwise its stimulant powers would make it less generally suitable than sulphuric acid; he gives 10 to 30 drops in mucilage (Journal de Chim. Medic., June, 1868). I have myself seen good results from the acid in purpura and passive hemorrhage, also in metrorrhagia.