Beccy
The book by Constance Radcliffe you refer to is called ''Ramsey 1600-1800 an includes many pages on the Black family.
A small passage-: Foremost among the Scottish incomers to Ramsey in the middle of the seventeenth century was John Black,who was a prosperous merchant and whose decendants were prominent in the town for nearly 200 years.... Black seems to have arrived in the island as a married man with a family of three sons and three daughters.
The earliest entries concerning the family in the Parish Register of Maughold are the burial of his wife Elizabeth in 1658 and the marriage of his daughters Elizabeth and Jane in 1659 to fellow Scots Edmund Gortry and Thomas Kelvie. John's second wife was an English woman, Grace Cook by whom he had three more daughters.
You need the book it has so much on the Black family.
Hope this little extract is of some help
Tom