Grammatically Correct: The writer's essential guide to punctuation ...

GRAMMATICALLY CORRECT
of what I myself witnessed while visiting at Aunt Verinder's house in
London. Pecuniary remuneration is offered to me-with the want of
feeling peculiar to the rich .... My nature is weak. It cost me a hard
struggle, before Christian humility conquered sinful pride, and self­
denial accepted the cheque.
-WILKIE CoLLINS, The Moonstone
Note that the distinctions between using dashes, conunas or parentheses
may not always be cut-and-dried, and you may sometimes
want to play with the different marks to see which effect looks best.
MARKING A BREAK IN STRUCTURE
OR TURN IN CONTENT
Dashes come in singles as well as doubles. Use an em dash if your
text is going along in one direction, then suddenly veers off in
another. That is, you can abruptly end a thought midstream, leave
it hanging and start another thought, all in the same sentence. There
must be some logical connectedness between what precedes and
follows the dash, but there does not have to be any grammatical
connectedness.
156
This hobbit was a very well-to-do hobbit, and his name was Baggins.
The Bagginses have lived in the neighbourhood of The Hill for time
out of mind, and people considered them very respectable, not only
because most of them were rich, but also because they never had any
adventures or did anything unexpected: you could tell what a Baggins
would say on any question without the bother of asking him. This is
a story of how a Baggins had an adventure, and found himself doing
and saying things altogether unexpected. He may have lost the neigh­
bours' respect, but he gained-well, you will see whether he gained
anything in the end.
The mother of our particular hobbit-what is a hobbit? I suppose
hobbits need some description nowadays ....
-J.R.R. ToLKIEN, The Hobbit
'I do appreciate, Mrs Sauskind,' continued Dirk, 'that the cost of
the investigation has strayed somewhat from the original estimate,