in order to irrigate his field, or to provide some other benefit;1 he ought not then to  be completely prevented from conducting it, or kept from conducting it conveniently  or in the proper way, according to the constitution2 of the servitude, as where, [when]  he ought to conduct it at all times, the other only permits him to conduct it at some  time, [or] if at certain times, not at any time.3 And so if he does not permit him to  conduct it in the quantity due, [or] to scour the channel, by which the flow of water  is impeded and the tenements of neighbours flooded. In all these cases a disseisin is  done the neighbour and he is protected [by the writ why he diverted a watercourse  to the nuisance of his free tenement,] by the writ, which will be given below.4 The  nuisances which destroy servitudes completely or, at the least, keep them from being  used effectively, are infinite, [It is clear that some nuisances are wrongful and harmful,  others harmful and not wrongful. Hence when a plaint of nuisance is made, we  must ask what harm is done and see whether it is harmful and wrongful. If so, it  must be removed; if not wrongful though harmful, it must be upheld.] as may be  seen. If one has the servitude of pasturing in another's land, he is entitled to free  ingress and egress. If he whose land it is does something to his means of ingress, so  that he can hardly enter at all, or only with greater inconvenience, as where he  builds a wall, a bank or a hedge, he commits a wrongful nuisance. What is thus done  may at once be undone and demolished, even without a writ, if action is taken while  the deed is still fresh;5 after time has passed, however, a writ will be necessary. And  so if the right of going over another's land is granted and the road is obstructed in  some way or narrowed, so that it may not be traversed at all, or only with difficulty.6  And so if the right to conduct water is granted, as above, and it is diverted, partially  or completely to the nuisance [of his free tenement]. 7 One may have common with  another [in many ways], a right of digging just as a right of pasturing, that he may  dig silver and gold, tin,8 chalk, stone, sand and the like in another's land.9 Similarly  a right of hunting and fishing, drinking and drawing water and many others, infinite  in number, with their appurtenances, that is with free access and departure, just as  free and adequate entry and exit are appurtenant to common of pasture. In all the  foregoing and many others the assise of novel disseisin would lie, just as for common  of pasture. And in the same way quo jure, if that were the usage.10
Or wrongful nuisances; of servitudes.
 And so if a servitude is imposed on another's land by law, not by man, as