In October 1842 William Henry Worth began an orderly compendium of dyed woolen yarn samples and recipes in a bound blank book. He provided no written indication why he was doing this, nor did he record and information about his profession. The book contains over180 yarn samples, three-quarters of which are accompanied by recipes listing ingredients. Comments on dyeing processes are included, but general instructions for dyeing are not. Three aspects of the book require investigation, 1) the book has to be put in its proper context; 2) the presence in the yarns of the ingredients listed in the recipes needs verification; and 3) the identity of dyes and dyeing aids in the yarns without recipes has to be determined. Only then will the value of this object to the conservation community be fully realized.