Another cause is when there are crude humours in the body, and they are not expelled by the urine, the faeces, or other arts787 whereby a man evacuates his excess matter from the body; and if they be expelled to the joints and remain therein, they putrefy.788 If they be evacuated in the urine, it will have a crude gross deposit;789 and the man who has this, will not contract the disease, for Avicenna and Galen say, those who fear an imposthume of the joints, if they give copious crude, raw urine, it saves them therefrom.