Dogs, like other animals, played a role in the warfare that should not be underestimated. They too were 'called to arms' in 1914, and helped the soldiers in a variety of ways. Behind the front, they were hitched to small carts, and in this way they transported machine guns, ammunition cases and food. After artillery fire, or in no man's land, dogs would track down the wounded. If they found someone, they would let their handler know without barking, so that the wounded person could be carried away. A dog could also pull one to two stretchers on wheels. As well as being ambulance personnel, a dog was also a messenger that could convey communications from one unit to another swiftly and unobserved, a rat catcher that helped the soldiers to keep the trenches rodent free, a guide that led patrols through terrain that was difficult to navigate, and a sentry that sounded the alarm when the enemy approached. But, for a good number of soldiers, the dog was also a welcome companion during long nights and moments of loneliness. Because they were so valuable, dogs even had special gas masks fitted to protect them.