Here’s an old fashioned remedy that I use to relieve my arthritis pains. I make what you call a mustard plaster. To do this you need to mix together 2 parts flour with 1 part mustard powder, then add some water to make a paste

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Mustard Plaster for Arthritis Pain

Drying and Preserving Roots, Herbs, Barks. General – collect herbs when the weather is good and when there is no dew on them. Dry them in the shade, after which they ought to be protected from exposure to the air by wrapping up inside paper or perhaps keeping in paper pouches, tied up and hung up

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Basic Harvesting, Processing and Preparation Of Medicinal Herbs