Here is the article for anyone that wants to read it. Although it claims it is 1945, it looks to be the same as the one you posted.
http://books.google.co.nz/books?id=qN8DAAAAMBAJ&pg=PA106&dq=bow&hl=en&sa=X&ei=mQiVU6b9HNHrkwXvzoHIBw&ved=0CCYQ6AEwADgK#v=onepage&q=bow&f=false"Boam" appears three times:
Once in the table, which advises that the thickness should be the same as Yew, but it should be slightly wider.
Here: "If you want the best, however, use osage orange or boam"
And here: "Yew and boam have more sapwood and will require trimming down"
From this we can deduce that:
- It has similar properties to yew, but needs to be made 1/16th of an inch wider for a given thickness, length etc.
- However, it is also considered to be "better" wood than Yew or lemonwood.
- It also has more sapwood than osage and lemonwood and requires similar treatment to Yew in that regard.
I'm not sure they are using "boam" to describe "other wood" in general with statements like that. Doesn't sound right.
Do these clues suggest any particular type of wood to you guys from USA? Do those clues fit Whitebeam, for anyone who is familiar with it?
There's a few hints in the article as you can see, so maybe we will solve it yet!