The rule of pleading as to multifariousness is founded on convenience—convenience to the defendant. McLean, Assignee, v. Bank of Lafayette, 4 McLean, 418; Fellows v. Fellows, 4 Cow. 682.
This rule forbids the joining of distinct and independent matters in one bill, and thereby confounding them; as, for example, the uniting in one bill of several matters perfectly distinct and unconnected against one defendant, or the demand of several matters of different natures against several defendants in the same bill. Story’s Eq. Pl. 271; Mitford’s Eq. Pl. 181.
Whether this rule applies to any particular bill or not is a question of fact—of fact, as to the nature and extent of interest of the complainant, or some of the complainants, in the causes of action; or of the defendant, or some of the defendants, as to the nature of the causes of action, whether they are distinct in character as well as independent in form, as to the scope of the relief prayed. Story’s Eq. Pl. 538, 540, 280. To lay down any rule applicable to all cases cannot well be done. Id. 539.
The cases upon the subject are various, and the courts, in deciding them, seem to have considered what was convenient under particular circumstances, rather than to have laid down any absolute rule. Campbell v. Mackay, 1 Mylne & Craig, 603. But it may be drawn from the cases, and is in accordance with the reason of the rule, that the test of multifariousnoss is: What is the burden imposed on the defendant ? to what defence is he forced ? can he make one defence to the *354whole bill? Attorney General v. St. John’s College, 7 Sim. 241; Story’s Eq. Pl. 530, 540; Daniell’s Ch. Pr. 334-346, notes 1 and 2. The facts, in this case present no complication.
The bill shows that re-issues Nos. 8,S91 and 8,896 are for improvements in fire alarms, and that the complainant has the right, under re-issue 4,588, of constructing apparatus for fire alarms and the transmission of municipal intelligence, and alleges that the defendant uses each of these inventions in one machine—uses them all in the same machine. It is plain, that the use of all these inventions together, to constitute a machine, is the cause of action set out in the bill; the construction of a fire alarm, such as defendant now uses, being the injury complained of and against which an injunction is prayed. Discovery is asked, not of how many machines containing separately the inventions in the several patents mentioned, but how many machines containing all these inventions used together to construct the machine, have been made.
A single defence—we do not make such a machine—meets the whole bill in its allegations and prayer founded on the allegations.
The mere setting out of more than one letters patent in a bill does not of itself render the bill multifarious. Case v. Redfield, 4 McLean, 526; Nourse v. Allen, 4 Blatchf. 376.
And it may be said generally that a demurrer for multifariousness will not lie to a bill founded on several letters patent, where all the inventions are set out as constituting one cause of action, and the prayer relates singly, as to discovery and remedy, to a machine constructed according to and containing all said inventions.
Where the discovery is prayed for under special interrogatories as to each letter patent in a manner so particular as to each invention that it is evident on the face of the bill that the relief sought is for infringement of each and every invention, and not for an injury arising from the making and using one machine constructed according tó such letters patent, the bill is demurrable.
To escape the objection of multifariousness such a bill *355should aver that said inventions are capable of conjoint as well as separate use, and are in fact so used by defendant. Nellis v. Lanahan, 6 Fisher, 286.
I.n the bill under consideration the letters patent are properly joined, and, in fact, constitute one and the same cause of action.
The demurrer is, therefore, overruled.
Baxter, G. J., concurred.
Note. Pleasants v. Glasscock, 1 Smedes & Marsh. Ch. (17 Ch. R. Miss.) 17; Dick v. Dick, 1 Hogan, (Rolls Court, Ireland,) 290; Salvedge v. Hyde, 5 Maddux, 138; Dawue v. Fanning, 4 John. Ch. 199; Varick v. Smith, 5 Paige, 160; Mitford’s Eq. Pl, § 181, note; Hayes v. Dayton, (S. D. N. Y., Nov., 1880, Blatchford, J.,) 18 O. G. 1406.