I found some old timetables with Reading and CNJ mileages (Reading owned the CNJ).
http://cprr.org/Museum/Books/I_ACCEPT_t ... e_1910.pdf
Look on page number 331 (as printed on the pages, not pdf page number) for the Reading RR Catawissa Branch:
Reading Station: MP 58.8, Tamaqua MP 98.3, Haucks MP 105.3, for difference =46.5 miles, from Reading to Haucks, although it's probably more like 43.5 from the new Reading Outer Station (north of Reading) that the Reading & Northern uses.
For the CNJ (Haucks to Mauch Chunk (now JIm Thorpe) they didn't have passenger service , so its not in the Official Guide for the CNJ (just before the Reading in the Official Guide.) Using Google maps I measure 17 miles.
So the trip total from Reading Outer Station to Jim Thorpe is ~ 43.5 + 17 = 60.5 miles. So for a 3-1/2 trip, that's ~17 mph.
*** Extra detail:
If you look on the CNJ pages, the CNJ coming west from Jim Thorpe (Mauch Chunk originally), initially on its Nesquehoning branch (now R&N) had passenger through service all the way to Tamaqua. See page 316. Mauch Chunk to Tamaqua = 15.5 miles according to that. Reading Outer Station to Tamaqua on the Reading is 36.5 miles. So that route would have been about 36.5 + 15.5 = 52 miles. Why the difference?
This latter CNJ route this went via Lansford and Coaldale (as noted in the Official Guide), meaning it left the Nesquehoning branch and took the old Lehigh and New England (or a predecessor??) direct to Tamaqua. That shortcut avoids the westward jog north of Tamaqua to East Mahanoy Jct. that the Reading (and modern R&N) take that NotYou mentions a few posts ago. The tracks from Lansford to Tamaqua are mostly still there, some of it was used occasionally for coal as of a few years ago at least. The tunnel north from Lansford to the ex-CNJ Nesquehoning branch was filled in, at least in the city of Lansdale [EDIT: should say "Lansford"], a few years ago:
https://www.tnonline.com/20180918/lansf ... el-filled/ , although no trains have gone through it in ~100 years or so I would guess.
Actually, I just found on the R&N map that the Lansford to Tamaqua section (ex LNE) is also owned by R&N now.
https://www.rbmnrr.com/system-maps
J.S.