After certain evidence had been put in without objection, tending to prove that the fire was set by means of a box containing a lighted candle and a quantity of combustible material; that the box and its contents were prepared for incendiary purposes, and were not adapted to any other purpose ; and pending also to prove that it was made at the defendant’s shop, where he had been at work secretly: the letter was admitted, subject to the defendant’s objection. The evidence tended to show that it was in the defendant’s handwriting. It was dated January 11; and the fire was set on the 16th. It contained a statement that the writer and another person had been engaged in setting fires to buildings by means of boxes; that they expected to receive more of suth boxes for incendiary purposes, an.< *457to use them for setting more fires and burning other buildings. It also refers to the burning of a church and a hotel by the same persons, and states the motive which had induced them to commit the offences already perpetrated and under which they were about to do the acts threatened. The admission of this letter was objected to; and it is contended that, even if a part of it is admissible, those parts which relate to the commission of other offences should have been rejected.
Certain other evidence was admitted, relating to what is called box No. 2, which it is contended should have been rejected on the same ground, namely, that it relates to other offences.
This box was found nearly a month before the alleged fire, in the rear of Harris Street Church. The evidence tended to show that it was like the box which was used to set the alleged fire, and was made at the defendant’s shop. Witnesses who were skilled in woodwork were called, who had examined a block contained in box No. 2, and had compared it with a stick found in the defendant’s shop, and were allowed to state their opinion that these pieces were originally parts of the same stick, and had been separated from each other. This evidence was objected to. But the court are of opinion that this is a subject in respect to which men of skill and experience may become expert, and that the jury may be properly aided by their opinions. The evidence was properly admitted.
The jury were carefully instructed in regard to the use to be made of this box and block, to wit, that if the jury should be satisfied that the defendant made them, the evidence was not to be used to show that he made the box used at the alleged fire, but only to show that he possessed the requisite skill, materials, tools and opportunity to have made it, and that this is its sole use, unless the jury should find, in the one, such marks as show that one hand must have made both.
The objection to all this evidence respecting the box No. 2, and the allusions to other offences contained in the letter, is urged upon the ground of a well established principle, that evidence which merely tends to prove that the defendant has committed some other similar offence, or which tends to prove facts that are *458merely collateral, is inadmissible. The principle is; that all the evidence admitted must be pertinent to the point in issue. But if it be pertinent to this point, and tends to prove the crime alleged, it is not to be rejected, though it also tends to prove the commission of other crimes, or to establish collateral facts. Thus, in Commonwealth v. Tuckerman, 10 Gray, 173,197, the defendant had prepared a paper in which he stated a large number of embezzlements which he had committed, and which were other than, those alleged; but one of the items was one of the alleged embezzlements ; and it was held that the whole paper was admissible. It was also held that other embezzlements than those alleged might be proved, as tending to establish the motive with which the defendant took the money alleged; the acts being so connected that the jury might find that the same intent applied to all of them.
In that case the principle is affirmed which is stated in Commonwealth v. Merriam, 14 Pick. 518, that evidence which tends to prove collateral facts is admissible, if it has a natural tendency to establish the fact in controversy, or if it has a natural tendency to corroborate other direct evidence in the case. The other cases there cited also illustrate the same principle. It was on this principle that evidence was admitted in Commonwealth v. Ferrigan, 44 Penn. State, 386, in a trial for murder, that an adulterous intercourse between the wife of the deceased and the prisoner had existed and continued to near the time of the homicide. The one crime furnished a motive for the other. In People v. Wood, 3 Parker Crim. Cas. 681, which was a trial for murder, proof of other crimes than that alleged, but connected with it by unity of plot and design, and influenced by a single motive, was held admissible. In Stout v. People, 4 Parker Crim. Cas. 71, it was held that it was not a valid objection to evidence otherwise competent, that it would tend to prove the prisoner guilty of a distinct and different felony.
The defendant’s counsel relies upon the expression of the court in Commonwealth v. Williams, 2 Cush. 582, that they do not sanction the admission of evidence merely tending to show that the defendant had in his possession instruments adapted to the *459commission of other crimes. But the evidence in this case did not merely tend to show this; it tended to show that the defendant possessed the requisite skill, materials, tools and opportunity to have made the box used to set the alleged fire; and in connection with the letter it tended to show that the defendant made both boxes with the single motive there stated. It tended to prove a use of his shop for the purpose of preparing boxes and materials for setting incendiary fires, including the fire alleged in the same place, and all instigated by one motive. In Commonwealth v. Wilson, 2 Cush. 590, the evidence respecting the key was held inadmissible, because it related to a distinct and independent transaction, not connected with the offence on trial. In Hill’s case, 20 Howell St. Tr. 1317,1355, evidence that the prisoner knew how to make the preparation of the combustibles that were used for setting the alleged fire was held to be material. It may also be shown that he possessed materials capable of being converted into instruments of the offence, including the means of their production, or that he made preparations for the commission of such a crime. Burrill on Circ. Ev. 260, 345.
Upon the principles above stated, we think all the evidence was properly admitted, and the instructions were sufficiently favorable to the defendant.
As to the alibi, the judge stated a proposition at first, which is abstractly true as applied to the position of the defendant’s counsel that the proof of it was conclusive, and that it was so strong as to leave a reasonable doubt in the minds of the jury. The proposition was, in substance, that if the defendant sought to establish the fact that he was at a particular place at a particular time, the burden of proof was upon him. But he modified this statement in respect to its bearing upon the burden of proof which was upon the government to establish the alleged fact that the defendant was present at the fire. The substance of the whole ruling was, i that if the evidence of the defendant which tended to prove an I alibi was such that, taken together with the other evidence, the jury were left in reasonable doubt as to whether the defendant was present at the alleged fire, they should acquit him. We cannot see that he has any ground to object to this ruling, for it left the *460evidence which tended to prove the alibi, even if it failed to establish it, to have its full effect in bringing into doubt the evidence tending to prove the defendant’s presence at the fire. We do not think that the instruction, taken together — the first part of it being so essentially modified by the last—violated any of the principles stated in Wilder v. Cowles, 100 Mass. 487.
Exceptions overruled.