Parents have a right to have their child baptised in the parish church of the parish in which they live or where they worship regularly.
If you live outside the parish but have good reasons for asking for your child’s baptism to be celebrated at St Mary's, Holy Trinity or St. Peter's. Please ask your local vicar for permission. The clergy of the Parish of Calne and Blackland can only minister to those outside with the blessing and goodwill of their parish priest.
Before going any further you might wish to have a look at the Church of England’s teaching and guidance on baptism. Please click http://www.churchofengland.org/weddings-baptisms-funerals/baptism-confirmation.aspx to be taken to the Church of England website.