This VANITY FAIR MAGAZINE article was published during the bloodiest year of the First World War and it lists a number of various services that dogs were trained to perform on behalf of their belligerent masters.
"The French war dogs are divided into five classes, each of which performs a special type of work. There are sentinel dogs, patrol dogs, ambulance dogs, dispatch dogs and drought dogs. In all these departments of military activity they have proved their worth."
Click here to read more articles about the dogs, pigeons and elephants that toiled throughout the First World War.