Grace fed chocolate to the hall porter's dog. At the time, it wouldn't be known that certain quantities of chocolate can be toxic to dogs, dark chocolates especially. The quantity is variable, depending on dog's weight and type of chocolate.
With dark (baker's) chocolate, use a scale of 1.5 ounces per 10 pounds of body weight --- that's 3 ounces for a 20-pound dog. If they've ingested that much or more, it's time to call your vet. With milk chocolate or semi-sweet, a poisonous amount would be anything over 3.5 ounces, a standard size Hershey's bar, for a small 10-pound dog. Or just dose with an emetic, such as ipecac syrup.
With dark (baker's) chocolate, use a scale of 1.5 ounces per 10 pounds of body weight --- that's 3 ounces for a 20-pound dog. If they've ingested that much or more, it's time to call your vet. With milk chocolate or semi-sweet, a poisonous amount would be anything over 3.5 ounces, a standard size Hershey's bar, for a small 10-pound dog. Or just dose with an emetic, such as ipecac syrup.