Orfila first described asphyxia as a result of injecting silver nitrate into the veins, and after death he found partial consolidation of the lungs, and excessive secretion in the bronchial tubes (Toxicology). Several observers have corroborated these results, and it has been a question whether they are mainly mechanical from thrombosis, etc., or reflex effects of lung-irritation (Charcot), or dependent upon direct irritation and paresis of the respiratory centre in the bulb, and of the neighboring vaso-motor centre. The recent observations of Rouget point to the latter conclusion. He found that in most animals urgent dyspnoea occurred, and, post-mortem, the lungs proved to be healthy in texture, but much contracted in volume - the muscular tissue of the bronchi being in a state of spasm similar to that of asthma. In adult specimens of only one order of animals (carnivora) did he find the excessive secretion described by Orfila, and he considered that only in these were the vasomotor centres affected. That the main effect is exerted on the central rather than on peripheral nerve-elements he further supported by showing that nerves and muscles retained electric excitability after death. Still more recent observations by Rozsahezzi on rabbits show that in chronic poisoning by silver there is constantly hyperaemia of laryngeal and tracheal membranes, also of the lungs, and in these organs often oedema was found, with congestion, ecchymoses, effusions, cheesy masses, and sometimes a condition resembling phthisis (Archiv Klebs, August, 1878).