in 1911, the Haarlem Committee of Supervision nominated his older brother, Derix, to continue restoring the city's twelve Hals group portraits. Like Carel, he worked at the Mauritshuis, developing a close professional relationship with then-director Wilhelm Martin that led to several collaborative projects, often scientific in nature. For example, in July 1916, in response to a threat of chemical attack, they tested the effects of lye on a series of "dummy" paintings in order to discover which brand of fire extinguisher was best suited to saving an artwork. Derix is also thought to have assisted Martin in his publications on conservation and restoration. In his continuation of the Hals project at Haarlem, he brought in the chemist Gosen van der Sleen to aid in his analysis. This was the first known case in the Netherlands of a chemist advising on a painting restoration project. With Van der Sleen's approval, he continued the restoration as planned, working with his son A.M., nephew C. F. Louis, and brother Carel to re-varnish the paintings. Although he published little himself, save for an article in the Kurt Walter Bachstitz Gallery Bulletin, he remained well-occupied with his restoration business in the Hague until his death on December 4, 1932. A. Martin de Wild Angenitus Martin de Wild, known as A. M. or Martin, was Derix de Wild's son. He sought to further the chemical approach to restoration promoted by his father and uncle. To this end, he enrolled at the Delft University of Technology, completing a doctorate degree in inorganic chemistry in 1928. His book The Scientific Examination of Pictures, originally completed as part of his chemistry thesis, was soon published internationally. Taking paint samples from a variety of European masterpieces, he studied the chemical makeup of synthetic pigments used in oil painting over time. After Martin's death, the book was considered a "landmark" for its technical analysis of pigmentation. Martin's heavily technical method of art analysis and formal chemical training were a relative novelty. He went on to some renown for his involvement in forgery trials throughout the 1930s and 1940s, including the highly publicized Otto Wacker trial in 1932 and the Han van Meegeren trial in 1946. He lectured at the University of Utrecht from 1938 until 1947. Working privately in his studio in the Hague, Martin published widely until his death in 1969, often collaborating with colleagues from the Delft University of