BLACKSTONE, Mass. — The squalid Massachusetts house in which the skeletal remains of three dead infants were found last month was to be torn down.The Board of Health in the city of Blackstone ordered the demolition, which was to begin Tuesday and was expected to take two days.Erika Murray, the woman who lived in the house with four children and her longtime boyfriend was being held on $1 million bail on charges including fetal death concealment.