I would keep giving the cat water (not milk) and bring a small bag of dry food along with you to leave for the cat as well. If you put out food at the same time every day, the cat will likely be waiting at that time. Are there any homes nearby? It's possible the cats and outdoor cat. Can you make up some fliers to post around if so? Call area shelters, and vets to see if perhaps somebody reported the cat as missing, and also place an ad in the newspaper under Lost & Found....most papers do this for free. Never describe the cat 100% but word it so the 'rightful owner' has to tell YOU details about the cats markings. This assures the person is genuine, and not grabbing the cat to sell to laboratories, or for fighting dog bait. Get the cat on a waiting list at shelters you contact as well. Many are overfilled, and unlikey to take cats until others are adopted to make space. Do you know anybody who's willing to house the cat until space opens in a shelter? Please try to get the cat into a safe haven before Winter strikes. It may not survive it. Keep us posted, and good luck, and also thanks for helping the cat...sounds like a beauty.