SummaryCutaneous temperature has been followed in normal people in order to study the effects of several tests abolishing arterial spasms. Vasodilatation by warm water and vasoconstriction by cold water are simple tests which do not need too much apparatus, but more patience.It makes possible to get some informations that are impossible to get by other methods. That is the reason why tests with barbiturates, tetra-ethyl-amnionium chloride or bromide or intra arterial injection of acetylcholine have been discarded. Warm and cold water tests have been considered as chief data in the diagnosis and prognosis of peripheral arteritis. It has the same value as arteriography and it is more useful than oscillometry.