The wool is an animal fiber with a chemical and physical properties: after shearing, the raw wool (or sucida) is very rich in lanolin, a waterproof fat substance, that practically disappears after washing. For this reason the raw wool has hydrophobic properties and doesn’t interact with the medicaments or the organic tissues (like the epithelial), whereas the washed wool has hydrophilic properties and absorbs the medicaments. In the Roman medicine the first type has been used like a mechanical means of transport or for covering, the second like an physical agent able to interactive with the medicaments. We can compare the kinds of the wool with the cotton, used now in medicine: the seed wool is hydrophobic, the cotton wool is hydrophilic
