I have a few things to look into. One was a note from the book The Politics Of Divine Wisdom. In that note the author refers to “TT Sept. 1913, 936” and seems to quote Johanna Farwerck-Borrius as the note says:
FARWERCK-BORRIUS, 4: ‘woman .. as far as self-sacrifice is concerned, surely in general, can and will give more than man.’
“TT” refers to The Theosophist an American Theosophical periodical. September 1913, page 936. I found that periodical online (it’s a fairly big PDF). Page 935 to 937 is a review of the book Theosophy and the Woman’s Movement, by C. Despard.
The quote would have fitted in a book like that, but I can’t find it! There is no Farwerck in this issue of The Theosophist, no Borrius and I even can’t find the quote that Herman de Tollenaere uses in his note.
So I looked up the book that is reviewed to see if maybe Johanna is quoted there. Also this book can be found online (again a fairly big PDF), but no Johanna in there.
I found the issue of The Theosophist on a website called The International Association For The Preservation Of Spiritualist And Occult Periodicals. I checked to see if Farwerck was mentioned anywhere and I got three results!
The first is a “general report of the 42nd convention of the Theosophical Society” of 1917 with reports of each country where the Society was active. Farwerck’s name is on the pages of the Netherlands! Unfortunately, the page that features his name is only half a page.
Judging the previous page, this means that there was a lodge in the town of Hilversum (where Farwerck lived), the lodge was called “Hilversum Lodge”, it was founded in 1903 and the president was F.E. Farwerck! Finally the proof that I’ve been looking for!
The author of The Politics Of Divine Wisdom has another note in which he seems to say that in Dutch Theosophical periodicals Farwerck is mentioned. In 1931 one supposedly says that Farwerck was a member of the “General Council” from 1917 and the note seems to imply that in 1917 there was also a mention of Farwerck. I haven’t found these issues yet to find out if De Tollenaere had a more helpful quote there.
But at least, proof enough of Farwerck’s Theosophical involvement. I’ll be looking for some more.
The other two results from the IAPSOP website were in French psychological periodicals which mention the foundation of the Coué foundation by the way. Farwerck is once named “M.E. Farwerck” and once “M. Farwerck”, but I’m quite sure that these are typos.