The opinion of the court was delivered by

On the showing made by plaintiffs as to the amount in controversy, the motion of defendant to dismiss is denied.

The first error .assigned is the striking out of three portions of the petition, viz.: (1) The description by subdivisions of all of a large tract of land (except one eighty-acre tract) which was alleged in the petition to belong to the defendant, “forming a tract which lies near and adjoining to the said property of these plaintiffs ;” (2) in the allegation that by its use and liability to explode the magazine was a common nuisance, a menace, etc., the words “a common nuisance;” (3) all of subdivision 8 of the petition. The first portion stricken out was the description of a large tract of land upon which it was alleged in subdivision 8 there were many locations, remote from highways and buildings, where a magazine could be erected with little danger to life or property.

In the determination of such a case a court of equity should consider just such facts as are here alleged. There is no claim that a cause of action was embraced in these allegations that was not in the original petition. If, as alleged, the building and the using of the magazine at the place intended would greatly endanger plaintiffs’ property and the lives of their family, and if, as alleged, the defendant owned other lands upon which, without great inconvenience, such magazine could be erected and used without danger or with much less danger to persons and property, a court of *68equity might well interfere by injunction. Also the allegation that the proposed building was, by reason of its use, a common nuisance seems entirely permissible, although the plaintiffs, to maintain the suit, would have to prove that they would be affected differently than the community in general by the alleged nuisance. So far we think the court was in error. If, as conceded, these facts were proper matter of proof, they were proper facts to plead. The latter part of subdivision 8, however, relating to the explosion of a magazine some time before, tendered no relevant issue and might well have been stricken out.

The court permitted Mr. Crane, who testified that he was an instructor in mining engineering in the University of Kansas, and who also testified to no inconsiderable amount of practical experience with explosives, to testify to many facts and numerous opinions relating to the effect of explosions of dynamite on persons and buildings at certain distances from the place of explosion. Many of these facts and opinions testified to were certainly matters of technical knowledge and science, and were proper matters of expert testimony; but the court afterward refused to consider this evidence, on the ground that the evidence was in effect a repetition of what the witness had read in books and was not based upon his personal observation and experience. In this there was error. The witness, in the main at least, did not undertake to repeat what any author or book said on a given subject, but gave his opinion from the weight of authorities as it appeared to him, necessarily calling his own experience to his aid in determining such weight.

Much space is devoted in the briefs to the discussion of the question whether the structure and the intended use thereof as alleged would make it a nuisance per se, or whether a careless or negligent use thereof would be requisite to make it a nuisance.

“A nuisance per se is an act, thing, omission, or *69use of the property which in and of itself is a nuisance, and hence is not permissible or excusable under any circumstances.” (21 A. & E. Encycl. of L. 683.)

A lawful business is not generally a nuisance per se, but may become so by being located in an inappropriate place or by being kept in an improper manner. (21 A. & E. Encycl. of L. 684, et seq.) It is therefore largely a question of fact whether the storing of a large quantity of dynamite in proximity to buildings is, when properly done, dangerous to the lives or property of persons located or living and passing within certain distances therefrom.

The evidence, or at least much of the evidence of the witness Crane, should have been considered and given such weight, if any, as it was entitled to in determining this question.

Other errors are assigned, but as the same questions are not likely to arise on a retrial they are not discussed. The judgment of the district court is reversed, with instructions to grant a new trial.