Ordnance Survey of the County of Londonderry. Colonel Colby Superintendent. Volume I. (Memoir of the City and North Western Liberties of Londonderry.

Account of the Operations Carried On for Accomplishing a Trigonometrical Survey of England and Wales

From the Commencement, in the Year 1784, to the End of the Year 1796: An Account Of The Operations Carried On For Accomplishing A Trigonometrical Survey Of England And Wales: From The Commencement, In The Year 1784, To The End Of The Year 1796

Ordnance Survey of the County of Londonderry. Colonel Colby Superintendent. Volume I. (Memoir of the City and North Western Liberties of Londonderry.

Account of the Operations Carried On for Accomplishing a Trigonometrical Survey of England and Wales

From the Commencement, in the Year 1784, to the End of the Year 1796: An Account Of The Operations Carried On For Accomplishing A Trigonometrical Survey Of England And Wales: From The Commencement, In The Year 1784, To The End Of The Year 1796