The people of Crema had remained faithful to the Milanese in their good and evil fortune; but the siege of that town presented fewer difficulties to the emperor than the siege of Milan. Crema was of small extent, and could be invested on every side; it was also more accessible to the engines of war, though surrounded by a double wall and a ditch filled with water. The Cremonese began the siege on the 4th of July, 1159; and on the 10th, Frederick arrived to direct it in person.[c] The emperor regarded the inhabitants of the town as revolted subjects and he probably expected to have little difficulty in accomplishing their overthrow. Contrary to his expectations, however, the Cremascans proved not only brave but stubborn, and despite his best efforts they held out against him for about six months. The siege gave rise to many picturesque incidents and furnished typical illustrations of the methods of warfare of the time. Even before the first attack Frederick sought to frighten the Cremascans into submission by the barbarous execution of several of their citizens who had previously been sent to him as hostages. Nothing daunted, the inhabitants of the besieged city retaliated in kind; moreover, they gave proof of their intrepidity by sallying forth and attempting to defeat a portion of the besieging army in open combat. Their small numbers rendered this an act of hardihood, but it evidenced the spirit in which they were prepared to repel the assault. Frederick, on his part, began the construction of the usual machines employed against walled cities. The chief of these consisted of great towers called cats, which were tower-like structures provided with battering-rams and with grappling-irons for tearing down walls. When these were ready, a road-bed was made for them by filling in the outer ditch with some two hundred casks and two hundred car-loads of gravel. Over this improvised causeway the largest cat was slowly rolled preparatory to the assault. The Cremascans marshalled themselves on the walls opposite this point of attack and assailed the cat with great stones hurled by catapults, and with showers of blazing arrows which had been dipped in a composition of oil, pitch, lard, and sulphur. These burning arrows were cut from the walls of the cat with scythes, but it was with difficulty that the flames could be extinguished, while the enemy’s projectiles threatened the complete destruction of the invading engine before it could be brought within close range of the walls.