There are many ways for commanders to gain the necessary information. They include the study of maps, information on previous battles (Napoleon was a keen reader of history), the use of local people, and of course spies. However, both before and during campaigns it is reconnaissance that predominates as the means of information gathering.
The following definition is taken from A Universal Military Dictionary by Captain George Smith, 1779:
Reconnaissance, in military affairs, implies to view and examine the state of things, in order to make a report thereof. Parties ordered to reconnoiter, are to observe the country and the enemy; to remark the routes, conveniences and inconveniences of the first, the position, march, or forces of the second. In either case, they should have an expert geographer, capable of taking plans readily: he should be the best mounted of the whole, in case the enemy happen to scatter the escort, that he may save his works and ideas.
An important element highlighted in this definition is the need to get
