We agree with defendant that this was a conclusion premised upon fact that was not present in the evidence. Oliver v. Pettaconsett Constr. Co., 36 R.I. 477, 90 A. 764; Eastman v. Dunn, 34 R.I. 416, 83 A. 1057. Nevertheless, we feel that the jury's decision as to defendant's negligence must stand for another reason.

It is a well-established rule that the admission of a hypothetical question ordinarily rests in the discretion of the trial justice and his ruling thereon will not be disturbed except for abuse of such discretion. Collins v. Gabrielle, 87 R.I. 235. Of course a hypothetical question not based on facts in evidence would be inadmissible and to allow it would be a clear abuse of discretion. Eastman v. Dunn, 34 R.I. 416. In the instant case, however, the full commission upon review of the record before the trial commissioner expressly found that the question propounded was based upon facts and reasonable inferences therefrom.

In our opinion, therefore, the testimony of Dr. Vargas on the ultimate issue before the commission was inadmissible because an expert may not give an opinion when the circumstances upon which it rests have not been supplied as facts in the case by competent testimony. Souza v. United Elec. Rys., 51 R.I. 124, 127; Eastman v. Dunn, 34 R.I. 416, 461. We come now to petitioner's contention that it was error to deny his motion to strike all of Dr. Vargas' testimony.

In Bull v. Mathews, 20 R.I. 100, 101, this court held that the common-law rule set forth in Chitty, supra, is the "ordinary test for determining whether different causes of action may be joined," and in Sowter v. Seekonk Lace Co., 34 R.I. 304, that a plaintiff could join in his declaration as many different causes of action as could be brought under one form of action. See Shipman v. United Electric Rys., 70 R.I. 454; Eastman v. Dunn, 34 R.I. 416; Sanitary Oyster Carrier Comm'n Co. v. Wm. M. Merwin Sons Co., 34 R.I. 381. Though we have found no case in this state nor has any been called to our attention where several distinct trespasses were joined in a single action of trespass, that this could be done at common law is abundantly clear for as stated in Stephen, Pleading (9th Am. ed.) 266, "if several distinct trespasses have been committed, these may all form the subject of one declaration in trespass * * *."

They declared on an express contract, the common counts and a count in indebitatus assumpsit and during the trial proceeded to offer the evidence which they possessed. In Eastman v. Dunn, 34 R.I. 416, which was an action of assumpsit, the defendant moved that the plaintiff be required to elect whether he would rely on the first two counts in special assumpsit or on the last two in indebitatus assumpsit. The motion was denied and an exception taken.

Whether or not a witness is competent to testify as an expert rests in the discretion of the trial justice subject to review by this court only for abuse of such discretion. Ennis v. Little Co., 25 R.I. 342; Eastman v. Dunn, 34 R.I. 416; State v. Prescott, 70 R.I. 403. In view of their long practical experience in handling dogs and in view of the nature of their testimony, which was not strictly medical testimony, the trial justice did not abuse his discretion in allowing the witnesses in question to testify as they did.

The trial justice found that he was so qualified. In this state it has been held that the competency of one offered as an expert is generally a question to be decided by the trial justice, and unless his ruling is palpably and grossly wrong it will not be reversed by the reviewing court. Eastman v. Dunn, 34 R.I. 416. Upon consideration we cannot say, in view of the record, that the ruling of the trial justice, in the present instance, was palpably and grossly wrong.

The parties being the same in each instance and the matters alleged growing out of the same transaction, a careful pleader will set forth his cause of action in different counts, so that if he fails of proof upon one count he may succeed upon another. Eastman v. Dunn, 34 R.I. 416, 438. Under our practice the declaration goes to the jury when the case is submitted to them for determination. A count which is not supported by proof is without legal force and apt to mislead the jury to draw inferences prejudicial to a defendant.

The general rule against admitting mere opinion as evidence without first establishing the experimental qualifications of the witness is a sound one where the occasion reasonably calls for its application, but in this state, unless the trial justice is grossly and palpably wrong in admitting such evidence, his ruling will not be reversed by this court. Eastman v. Dunn, 34 R.I. 416, 456. In the present instance it appears, from the witness's answers to the question objected to and to other questions asked prior thereto without objection, that he was possessed of some knowledge of the effects upon the human anatomy of bullets fired from a gun.

The allowance or refusal of a motion to amend pleadings is a matter within the discretion of the presiding judge, and no appeal lies. State ex rel. Goodwin v. Caraleigh Phosphate Fertilizer Works, 123 N.C. 162, 31 S.E. 373; Eastman v. Dunn, 75 A. 697. In Standard Encyclopedia of Procedure, vol. 2, page 162, it is said: