On the one hand, the Nai or barber, the Kahar and Dhimar or watermen, the household servants, the Bari, Ahir, and others, some of the village priests and the gardening castes, are considered ceremonially pure and Brahmans will take water from them.

But this is a matter of convenience, as, if they were not so held pure, they would be quite useless in the household.

Several of these castes, as the Dhimars, Baris and others, are derived from the primitive tribes.

Sir H.Risley considered the Baris of Bengal as probably an offshoot from the Bhuiya or Musahar tribe: "He still associates with the Bhuiyas at times, and if the demand for leaf-plates and cups is greater than he can cope with himself, he gets them secretly made up by his ruder kinsfolk and passes them off as his own production.

Instances of this sort, in which a non-Aryan or mixed group is promoted on grounds of necessity or convenience to a higher status than their antecedents would entitle them to claim, are not unknown in other castes, and must have occurred frequently in outlying parts of the country, where the Aryan settlements were scanty and imperfectly supplied with the social apparatus demanded by the theory of ceremonial purity.