In his first assignment of error, defendant contends that Judge Bailey erred in dismissing his application for a writ of habeas corpus. We disagree.
The Interstate Agreement on Detainers has been adopted by North Carolina and codified as G;S. 15A-761. Article IV (c) of the Agreement provides:
“In respect of any proceeding made possible by this Article, trial shall be commenced within 120 days of the arrival of the prisoner in the receiving state, but for good cause shown in open court, the prisoner or his counsel being present, the court having jurisdiction of the matter may grant any necessary or reasonable continuance.”
Defendant was first brought to trial on 13 April 1976, well within the 120-day limit of Article IV (c). Because of the mistrial, defendant had to be retried on 14 June. As defendant would have it, his trial did not commence until 14 June, after the 120-day period had expired. This contention, however, overlooks the effect of a mistrial upon defendant’s statutory right to disposition of the charge. In State v. George, 271 N.C. 438, 156 S.E. 2d 845 (1967), our Supreme Court held where a criminal defendant is tried within the period prescribed by the Interstate Agreement oh Detainers and such trial results in a mistrial, he is not subsequently entitled to have the charges *348dismissed even though the second trial occurs after the prescribed time limits, so long as the State uses due diligence in prosecuting the case.
“ . . . The State, of course, cannot control the fact that a jury is unable to agree upon a verdict and is not chargeable with responsibility under these conditions. In 22A C.J.S. 60, Criminal Law § 472(3), it is said: Tf accused is tried within the statutory time . . . and such trial results in a mistrial, as when the jury failed to agree, accused cannot ignore the mistrial and claim a discharge or dismissal upon the ground that he was not tried within the time fixed by the statute providing for that relief. . . . (W)hile accused is entitled to a speedy retrial by virtue of the constitutional or statutory guaranty of a speedy trial, the statute providing for a discharge or dismissal if accused is not tried within a stated time does not govern the time within which a retrial must be had, and the time for a retrial is a matter of judicial discretion.’ ” 271 N.C. at 442-43, 156 S.E. 2d 848.
We have reviewed Judge Bailey’s order and find no error or abuse of discretion in granting the State an additional 90 days in which to retry the case. Accordingly, this assignment is overruled.
Prior to trial, defendant discovered that, due to circumstances beyond his control, one of his witnesses, Judith L. Chandler, would be unable to testify at trial. Chandler’s testimony would have related to defendant’s physical appearance at the' time of the robbery and contradicted the testimony of the eyewitnesses. He moved for a continuance, and, by order of 14 June 1976, the trial court denied the motion. In his second assignment of error, defendant contends that the denial of his motion for continuance constitutes prejudicial error. We disagree. It is well settled that a motion for continuance is addressed to the sound discretion of the trial court and its ruling thereon is not subject to review absent an abuse of discretion. State v. Hill, 287 N.C. 207, 214 S.E. 2d 67 (1975); State v. Baldwin, 276 N.C. 690, 174 S.E. 2d 526 (1970). Defendant claims that Chandler, who had been his parole officer in Virginia, would have been his most credible witness because his other witnesses had criminal records. However, defendant’s witnesses testified as to his appearance on the date of the robbery. Under these cir*349cumstances we find no abuse of discretion in the denial of the motion. State v. Henderson, 216 N.C. 99, 3 S.E. 2d 357 (1939); State v. Shirley, 12 N.C. App. 440, 183 S.E. 2d 880, cert. den., 279 N.C. 729, 184 S.E. 2d 885 (1971). This assignment is overruled.
In Sprague’s testimony, she stated that she observed defendant from a distance of one and one-half feet during the robbery. In her description to the police, she did not mention that defendant’s nose was unusual. However, defendant introduced testimony that he had broken his nose as a child and that it had since remained deformed. Defense counsel interrupted Sprague’s testimony and requested that the jury be allowed to see defendant and Sprague in close proximity to each other. The court denied the motion and defendant assigns the denial as error. He contends that the demonstration would have enabled the jurors to see better the deformity of defendant’s nose and to conclude that Sprague’s identification of defendant without mention of his nose was inadequate. Where there is no controlling statutory or procedural rule, the conduct of a trial rests in the sound discretion of the trial court. Shute v. Fisher, 270 N.C. 247, 154 S.E. 2d 75 (1967); Frazier v. Glasgow, 24 N.C. App. 641, 211 S.E. 2d 852, cert. den., 286 N.C. 722, 213 S.E. 2d 721 (1975); 7 Strong, N.C. Index 2d, Trial, § 5, p. 261. Included in the supervisory power of the trial court is the discretion to control the method of the examination of witnesses. 1 Stansbury, N. C. Evidence, § 25, p. 59 (Brandis Rev. 1973). Here defendant does not contend that the jury did not have an otherwise adequate opportunity to view the condition of his nose. Moreover, there was no evidence tending to show that Sprague had any difficulty in identifying defendant as the robber of the store. Under these circumstances, we hold that the trial court did not abuse its discretion in denying defendant’s motion.
Defendant’s remaining assignments relate to the instructions to the jury. The charge of the court must be read as a whole, and a new trial will not be granted, even where there is technical error, where it clearly appears that the error is not substantial and could not have affected the result. State v. Hall, 267 N.C. 90, 147 S.E. 2d 548 (1966). Moreover, the record reveals that defendant did not bring the alleged errors to the trial court’s attention prior to the time the jury began its deliberations. “As a general rule, objections to the statement of *350contentions and to the review of the evidence must be made before the jury retires, or they are deemed to have been waived.” State v. Ford, 266 N.C. 743, 746, 147 S.E. 2d 198, 201 (1966). We have examined the charge, however, and hold that it contains no error prejudicial to defendant. These assignments are overruled.
No error.
Judges Hedrick and Arnold concur.