by which both may1 be determined, the act itself as well as the means and quality,  for the principal matter ought always be decided first, with which the accessory may  be decided. For example, if one has been disseised of a tenement by force and arms  and impetrates a writ quare vi et armis, it ought not to be good, because the question  is then one as to the kind of disseisin, not as to the thing itself, that is, the tenement  for which the force took place, nor does the plaintiff acquire any part of that tenement.  But if several writs are impetrated with respect to a single act which gives rise  to several actions, as several disseisins, and they may be determined by one writ and  one action, if that is so done, the other writs and actions do not fall but are determined,  and will henceforth be superfluous.2 Note that an exception may be peremptory to  the writ and not to the right, because sometimes one action3 for recovering the thing  is changed to another because of the privilege of heirs; the writ on the possession falls  completely and he is thrown back to the right, [because] the assise of mortdancestor  does not lie between coheirs and persons connected by blood, only the writ of right.4  Also [an exception] may be peremptory both to the writ and to the right, by the  exception of res judicata, of recognition, of remission and quitclaim. In every case  where an action is destroyed, the writ is destroyed, but not conversely, as was said  above.5
What a writ is, and which are original and which magistral.
 6A writ is formed in the likeness of a rule of law, since it briefly and in a few words  expounds and explains the intentio of him who puts it forward, like a rule of law,  [which] expounds the matter briefly.7 It ought not, however, to be so brief as not to  contain the reason and gist of the intentio. Some writs are formed on specified cases  and are of course. They are granted and approved by the counsel of the whole realm  and can in no way be changed without their consent and agreement.8 There are also  writs following from them, called judicial writs, which are often varied according to  the variety of pleas