Agency vs Structure

I went back to Anthony Giddens this week, to read more on the different approaches to the reconcialiation between agency and structure. I am trying to think how the history I am writing of Barbosa du Bocage's life is (or not) helped by the Bourdieu concepts of field and capital, and how am I going to address the concept of habitus. 
In fact, I was moving away from the concept of habitus, which I found hard to use in my text. My writing became much more fluid when I introduced the concept of scientific persona (that I borrowed from Lorraine Daston's reading of Marcel Mauss). This is now the main point from where my dissertation starts to make sense (I hope). The role implied in the concept of persona seems much more intuitive to use in my case-study. 
With this concept I can describe how this naturalist build his carreer around the specific ethos of the scientific work; And how this construction in turn relates with his political participation in matters of colonial administration and colonial science. 
In order to relate Bocage's participation in two distinct social fields, I have to find a bridge between the two spheres. Bocage was never a public man, although he involved himself in several institutions and had a political chair as a nation deputy, he didn't participate in the public sphere by writing in the newspapers or using science education and popularization as a tool for progress and regeneration of the country - like many of his generation. 
And yet, the bridge between fields materialized.