A seven-year old boy from Loudonville who was diagnosed last year with Batten Disease, a rare nervous system disorder that robs people of their site, is now an author  Peter Heath, who went blind from the disease, released his book “The Adventures of Marshmallow and Peter” earlier this month.  Heath and his family held a book signing Friday at the Loudonville Public Library, where copies of his book sold out in less than two hours.  Peter says he plans to continue writing new books and is already working on one based on a recent trip to Disney World.  “The Adventures of Marshmallow and Peter” is available to purchase at Barnes and Noble and online on Amazon.