suggest you also check with UK PRO - my own guess is that your first Newnham came with the formation of the RN Volunteer Reserve in Peel - they set up on Battery Head c. late 1890's I think - somewhere I have the info (I think in one of the Postcard view books which shows a photo in early 1900's of the group and prob thus your grandfather).
Teare is a very common name - the census will normally give reported age - suggest you then search all putative Teares via IGI and then see if their parents left any wills - all this can be done online (family search) or via local FHC and Brian Lawsons combined index to wills