Thank you for your response to my posting on genforum re Hallen.
In fact, if your wife's people were British people (here I use the official definition of that word) surnamed Hallen (Hallan may not be covered) it is quite likely that they were descended from the van Halen family members who made the journey from the Low Countries to England in the early 17th century.
I have in fact managed to locate a copy of the Revd A.W. Cornelius Hallen's work on his family. It is in the catalogue to be found on-line at familysearch.org, the Mormon website for genealogy. The microfilmed copy was missing pp. 34 & 35, but otherwise traces the family from Great Britain back to the present-day kingdom of Belgium where the family was indeed called van Halen (or van Hallen). The original surname of the family was Mirabello as the Belgian family was founded by an immigrant from Lombardy in Italy. This was francisized to de Mirabelle dit van Halen as French and Flemish were both in use in Malines (Mechelem) where the family flourished.
Please feel free to use my email address to respond with fuller details of your wife's family so that I can try to make the connexion to the people in the book. You can find it by clicking on my name above.
Richard Carruthers Vancouver,British Columbia, CANADA