Sir, – The arguments against the building of the New National Children’s Hospital on the Mater Hospital site have been forcefully made by your environmental editor, Frank McDonald (Opinion, December 5th). Even if An Bórd Pleanála should decide to grant permission for this oversized development on a severely restricted site it will still require a political decision to proceed. This decision should not be given for all the reasons so cogently expressed by Frank McDonald. – Yours, etc,