When it was necessary that what was at that time a most difficult and dangerous surgical operation should be performed upon Louis XIV, enquiry was made for men afflicted with the same disease, they were conveyed to the house of the minister Louvois, and there in presence of the King's physician Fagon, Felix the chief surgeon operated upon them. Most of these patients died; they were interred by night, but notwithstanding all precautions it was observed that dead bodies were secretly carried from that house, and rumours got abroad that a conspiracy had been discovered, that suspected persons had been brought before the minister and had either died under the question or been made away with by poison under his roof. The motive for this secresy was that the King might be saved from that anxiety which the knowledge of what was going on must have excited in him. In consequence of these experiments, Felix invented new instruments which he tried at the Hotel des Invalides, and when he had succeeded with them the result was communicated to the King, who submitted to the operation with characteristic fortitude. The surgeon performed it firmly and successfully; but the agitation which he had long struggled against and suppressed, produced then a general tremour from which he never recovered. The next day, in bleeding one of his own friends he maimed him for life. This was a case in which the most conscientious practitioner would have felt no misgiving; there was no intentional sacrifice of life, or infliction of unnecessary suffering. So too when inoculation for the small-pox was introduced into this country; some condemned criminals gladly consented to be inoculated instead of hanged, and saved their lives by the exchange.