(Oooo, a puzzle that needs solving!!)
Hi Plsllyn,

with ziggy9 on the date.
W / NO 26 / 95 / RY.P.O.
= West-bound Train / November 26, 1895 / Railway Post Office
An RPO cancel. Usually these say RPO but some do say RY PO. Or even M.C. (Mail Coach), STN. (Station) or others. The & symbol is a dead give-away that it's an RPO, or a traveling Railway Post Office on a railway car or coach. (called TPO in Great Britain.)
The place names are difficult (easier if you had it in hand so you could tilt it in the light and twirl it around so the letters are upright when trying to read them. But . . .
ST(.)H (or N) **NS & (and) (the character above 'W') E (or F) C(?) *****(?)
(The) St.(Saint) H**NS &(and) FO***** (Railway) (?)
If one had a listing of Quebec (or New Brunswick) Railway cancels (from the old Ludlow catalog or the newer Gray(?) catalog) I think you could start comparing names and see which ones had RY PO first and then the ones that had two place names in the cancel name. It would narrow down quickly.
The letters that I guessed are only approximate. It helps a lot if you know the place names (say from the area where you live or know well). I am not too familiar with the French place names myself. Mostly Nova Scotia.
Examples of RPO cancels:

Envelope Back-stamped Transit Marking ’ANNAPOLIS & YARMOUTH / EAST / DEC 25 / 95 / M.C.’
on the train travelling East from Yarmouth towards Annapolis Royal, Nova Scotia in 1895 on Christmas Day.

Interesting Transit mark’TOR.& MONT. G.T.RY / D.E. / DE 14 / 95 / 11
(Toronto and Montreal Grand Trunk Railway (Dead Ender? Destination East? Destination de l'Est?) December 14, 1895, Hammer 11)

HALIFAX & TRURO / 6 / JUL 3 / 39 / RPO.
Halifax and Truro (Nova Scotia), Train 6, etc

INVERNESS & PT.(Point)TUPPER / 156 (Train Number) / JUN 19 / 39 / * RPO * (In Nova Scotia)