The answers to questions like these and hundreds more can be found in The Complete Book of Incense, Oils and Brews by world-famous author Scott Cunningham. This is a greatly expanded and rewritten version of The Magic of Incenses, Oils and Brews. It includes over 100 new formulas, proportions for each element of the recipes (the most requested feature from his previous book), how to substitute ingredients, and much more. Besides the formulas, it also includes the exact methods of making all of these scented tools, including how to extract the essences from the herbs.