Juan Luis Delgado

Juan Luis Delgado

Juan Luis Delgado

Doan Fellow


Since September 2009 I have been a Ph.D. student in the Contemporary History Department in Autonomous University of Madrid with the project “Historia técnica de la resina en España, siglos XIX y XX” [Technical History of pine’s resin in Spain, 19th–20th centuries]. For the last two years I have been a scholarship holder of Consejo Nacional para la Ciencia y la Tecnología, México [National Council for Science and Technology].

The Ph.D. thesis continues the final paper of my master’s degree to the second half of the 20th century—when the “traditional” tapping method was replaced by a modern one using chemical stimulants—and also in perspectives and sources. Legal, industrial, economic, forestry, and scientific sources are expanding the research path started with patents.

Meanwhile, I am in charge of  the review section of a digital journal for young researchers, Revista Historia Autónoma [Autonomous History Journal], which is published by the History Postgraduate Students Association of the Faculty of Philosophy in the Universidad Autónoma de Madrid. I am also a member of the Postgraduate Commission in Contemporary History Department, representing Ph.D. students since spring 2011.

Summary of My Research

I will be researching part of my Ph.D. thesis in which I am trying to explain the socio-natural environment of the creation and improvement of technique applied in Spain during the 19th and 20th centuries to tapping gum resin from living pine trees, and distilling it to produce turpentine and rosin.

The Spanish gum-resin industry has been studied by a minor number of researchers; however, all of them have only mentioned that this industry is one relevant branch of the chemical industry. The role of this industry within the Spanish forest and chemical history is still to be determined. In relation to chemical history we do not know anything, either industrial or scientific; we just identify chemical industries in which turpentine and rosin were, or have been, important, e.g., paints, varnishes, paper size, inks, soaps, and so on. So we ignore how these by-products helped improve the production of those industries. Specifically I am interested in the soap industry because of its close relation with the olive oil industry, which is very important in Spain.

Another very relevant topic that I want to investigate in this specific project focuses on the development of the tapping method known as bark chipping, with chemical stimulation during the 1940s and 1950s in the United States. The necessity of increasing yield production of gum resin became one of the principal goals of people involved in the industry, among other reasons because labor costs began to rise and as a consequence the profit began to decrease.


Twitter: @morralejo