Kautilya's Arthashastra 8.1.35

8.1.35

durgaḥ kośād upajāpyaḥ pareṣām //

Pisuna says that of the troubles due to the absence of forts and to want of finance, troubles due to want of finance are more serious; the repair of fortifications and their maintenance depend upon finance; by means of wealth, intrigue to capture an enemy's fort may be carried on; by means of wealth, the people, friends, and enemies can be kept under control; by means of it, outsiders can be encouraged and the establishment of the army and its operations conducted. It is possible to remove the treasure in times of danger, but not the fort.