1904-1997 20thcentury 751 agriculture aménagement analysis analytic art artists botany chemicalprocesses chemistry conservation conservationandrestoration dekooning drawing dutch earlyworksto1800 engineering england environmentalconservation etc general handbooks healthandhygiene industrialdesign lifesciences london manuals matérield'artistes methodology modelsandmodelmaking modern motives museumconservationmethods nature netherlandish organic painting paintmaterials pigments protection prototypes safetymeasures science soilconservation soilmanagement sols technique technology themes toxicology watercolorpainting willem