And, in point of fact, there was a time when the service of a surprise and that of espionage were so far regarded as the same that by the laws of war death was not only the allotted portion of the captured spy but of all who were caught in an endeavour to take a place by surprise. The rule, according to Vattel, was not changed, nor the soldiers who were captured in a surprise regarded or treated as prisoners of war, till the year 1597, when, Prince Maurice having failed in an attempt to take Venloo by surprise, and having lost some of his men, who were put to death for that offence, the new rule that has since prevailed was agreed upon by both sides for the sake of their future mutual immunity from that peril. The usual rule laid down to distinguish a bad from a good stratagem is that in the latter there is no violation of an expressly or tacitly pledged faith. The violation of a conference, a truce, or a treaty has always therefore been reprobated, however commonly practised. But certain occurrences of history suggest the feasibility of corresponding stratagems which cannot be judged by so simple a formula and which therefore are of still uncertain right. The first stratagem of this kind that suggests itself is that of forgery. Hannibal, having defeated and slain the Roman general Marcellus, and thereby become possessed of his seal, the Romans found it necessary to despatch messages to all their garrison towns that no more attention should be paid to orders purporting to come from Marcellus. The precedent suggests the use of forged despatches as a weapon of war. To obtain in time of peace, for use in time of war, the signatures of men likely to be hostile commanders, would obviously be of immense military service for purposes either of defence or aggression. The stratagem would be dishonourable in the highest degree; but, unfortunately, the standard of measurement in such cases is rather their effectiveness than their abstract morality. The second stratagem of the sort is the stratagem of false intelligence. To what extent is it lawful to deceive an enemy by downright falsehood? The Chevalier Bayard, ‘without fear or reproach,’ when besieged by the Imperialists in Mézières, contrived to make the enemy raise the siege by sending a messenger with letters containing false information destined to fall into the hands of the enemy. The invention of the telegraph has increased the means of deceiving the enemy by false intelligence, and was freely so used in the Civil War of the United States. It is said to be better to secure the services of a few telegraph operators in a hostile country than to have dozens of ordinary spies; and for this reason, according to the eminent author of the ‘Soldier’s Pocket-Book’: ‘Before or during an action an enemy may be deceived to any extent by means of such men; messages can be sent ordering him to concentrate upon wrong points, or, by giving him false information, you may induce him to move as you wish.’