Defendants assign as error the admission of testimony by the Virginia State trooper of his observation of the load of hams in the cargo bed of the truck. They argue that the hams were not in “plain view” of the trooper because he had to climb up on the wheel or axle of the truck to see over the wooden siding. They argue, therefore, that the hams were discovered by means of a search which was not reasonably related to the offense for which All was arrested, which was not for purposes of protection or prevention of escape, and which was not founded on probable cause; and, consequently, was a search prohibited by the Fourth Amendment to the Constitution of the United States.
It seems to us that the arguments advanced by defendants are wide of the mark. In this instance, the officer knew he must impound the truck until the windshield could be repaired. Under such circumstances it was his duty to take reasonable precautions to protect defendants’ cargo from loss or destruction. Also, it was his duty to protect himself and the State from charges of loss of cargo. In order to do these things it was necessary for him to know the nature and quantity of the cargo. His conduct in looking into the cargo bed was both reasonable and necessary under the circumstances. If his action can be classed as a search, it was certainly a reasonable search. It is only unreasonable searches which are prohibited by the Fourth Amendment, State v. Ratliff, 281 N.C. 397, 189 S.E. 2d 179. Once the trooper acquired knowledge of the cargo by a reasonable act, he was not required to suppress this knowledge when the police radio bulletin later advised of the theft of a quantity of Hickory Mountain Farms hams.
The numerous cases relied upon by defendants are distinguishable upon the reason for the “search.” For cases more comparable to the present case See 10 ALR 3d 314-354, § 9 [New] Making inventory of contents of impounded vehicle (Supp. 1972). In our opinion, the trooper’s testimony concerning the load of hams was properly admitted in evidence.
 Defendants next argue that the bolt cutters taken from the truck were found as a direct result of an illegal confession and, therefore, should have been excluded from evidence as was the confession itself. While there seem to have been sources of knowledge of the bolt cutters equally as clear as that obtained from the excluded confession, we do not feel it is necessary to *287dwell upon the question in this case. Conceding, arguendo, that the bolt cutters were the fruit of an illegal confession, their admission in evidence would constitute harmless error beyond a reasonable doubt. The remaining evidence against defendants was more than sufficient to support their convictions: a truck similar to theirs was seen driving from the vicinity of the break-in; the unequivocally identified stolen hams in defendants’ possession in Virginia a few hours after the break-in; and fibers found at the scene of the break-in which matched one defendant’s sweater. If it were error to admit the bolt cutters in evidence, in view of the total evidence, we hold such error to be harmless beyond a reasonable doubt. See Harrington v. California, 395 U.S. 250, 23 L.Ed. 2d 284, 89 S.Ct. 1726; State v. Doss, 279 N.C. 413, 183 S.E. 2d 671; State v. Bell, 14 N.C. App. 346, 188 S.E. 2d 593.
We have carefully considered defendants’ assignment of error relating to the allowance of opinion testimony by one of the State’s witnesses. Without belaboring the point, it is our opinion the evidence justified the trial court’s finding that the witness was qualified to testify in the field of forensic chemistry. This assignment of error is overruled.
Judges Campbell and Graham concur.