On trial to a jury, the defendant was convicted of the crimes of robbery in the first degree in violation of General Statutes § 53a-134 (a) (3), and of conspiracy to commit robbery in the first degree in vio*301lation of General Statutes §§ 53a-48 and 53a-134 (a) (3). He appeals from the trial court’s refusal to set aside the jury verdict and render judgment of acquittal on both counts. His appeal is based on two alternative claims: That the evidence was insufficient to identify him as a participant in the robbery; and that the pellet gun used in the robbery was not a dangerous instrument as defined by General Statutes § 53a-3 (7).
The jury could reasonably have found the following facts, among others. On the night of May 11,1986, two masked males robbed a convenience store in Manchester. The first robber, wearing a clown mask and carrying a pellet gun, leaped over the cashier’s counter and ordered the store clerk to open the cash register and the safe. The second robber, wearing a red scarf over his face and carrying a tire iron, approached the store clerk’s husband and ordered him to lie facedown on the floor. The robbers took approximately $100. The clerk and her husband were not injured.
The store clerk and her husband provided the jury with profiles of the robbers through their testimony at trial. The first robber was between 5'6" and 5'8" tall and slight of build. The second robber was about two inches taller than the first. The first robber wore a clown mask that was bald on top with red hair sticking out on the sides. He also wore grey sweat pants. The pellet pistol he carried was black with a brown handle and a screw at the bottom of the handle.
A police investigation linked the defendant to the robbery. The defendant and a close friend lived in the same neighborhood, approximately two miles from the convenience store that was robbed. The defendant is approximately two inches shorter than his friend, who is nearly six feet tall. The defendant often wore grey sweat pants. The defendant had a pellet pistol similar *302to the one used in the robbery, which he turned over to the police before his arrest.
At trial, the state’s witnesses produced testimony that further linked the defendant to the robbery. The mother of the defendant’s friend testified that, about one month before the robbery, she discovered a pellet pistol in her apartment and, after her son told her that the pistol belonged to the defendant, she ordered her son to return it. She also testified that her son brought home an expensive stereo, leather jacket and leather sneakers and seemed to have money although he was unemployed. Other witnesses testified that the defendant possessed a pellet pistol and a Halloween costume prior to the robbery. Also, the defendant and his friend were heard asking for money on the day of the robbery.
I
The defendant first claims that the state’s evidence was insufficient to identify him as a participant in the robbery. Among the essential elements of the crimes charged, which the state had the burden of proving beyond a reasonable doubt at trial, is the identification of the defendant as the first robber. State v. Jackson, 176 Conn. 257, 258, 407 A.2d 948 (1978).
Our standard of review is well settled when the sufficiency of the state’s evidence is challenged after a conviction. We first construe the evidence in the light most favorable to sustaining the verdict. On the basis of this view of the evidence, we then determine whether the jury could reasonably have found guilt beyond a reasonable doubt. State v. Braxton, 196 Conn. 685, 691, 495 A.2d 273 (1985).
Our role is to determine whether the jury could have logically reached its conclusion from the facts shown. The jury must find guilt beyond a reasonable doubt by using the evidence to exclude every reasonable hypothe*303sis of the defendant’s innocence, but it need not exclude every possible supposition of innocence no matter how implausible. State v. Foord, 142 Conn. 285, 295, 113 A.2d 591 (1955). The jury may draw reasonable inferences from the proven facts, but must not resort to speculation. State v. Gaynor, 182 Conn. 501, 503, 438 A.2d 749 (1980).
If we find that there is sufficient evidence to enable the jury to find guilt beyond a reasonable doubt without resorting to speculation, the conviction must stand. We must not invade the province of the jury by weighing the evidence or by resolving questions of the credibility of witnesses. State v. Cobbs, 203 Conn. 4, 6-7, 522 A.2d 1229 (1987). “We do not sit as a thirteenth juror who may cast a vote against the verdict based upon our feeling that some doubt of guilt is shown by the cold printed record.” State v. Stepney, 191 Conn. 233, 255, 464 A.2d 758 (1983), cert. denied, 465 U.S. 1084, 104 S. Ct. 1455, 79 L. Ed. 2d 772 (1984).
In the case before us, it is of no moment that the eyewitnesses were unable to identify the defendant as a participant in the robbery. The state’s case was necessarily based on circumstantial evidence because the robbers wore masks. There is no difference in the degree of the probative force of direct evidence versus circumstantial evidence. Id. However, because “the force and effect of circumstantial facts usually, and almost necessarily, depend upon their connection with each other”; Moore v. United States, 150 U.S. 57, 61, 14 S. Ct. 26, 37 L. Ed. 996 (1893); we recognize that “[i]t is not one fact, but the cumulative impact of a multitude of facts which establishes guilt in a case involving substantial circumstantial evidence.” State v. Cimino, 194 Conn. 210, 211, 478 A.2d 1005 (1984).
The cumulative impact of the evidence in this case was sufficient to enable the jury to conclude beyond *304a reasonable doubt that the defendant participated in the robbery. The defendant and his friend fit the description of the robbers. They lived within two miles of the crime scene. The mother of the defendant’s friend gave testimony that strongly suggested that the two were involved in illegal activity. The defendant was in possession of a pellet pistol similar to the one the store clerk and her husband described. He also possessed some sort of Halloween costume with red hair on it, similar to the red hair on the clown mask the first robber wore. Finally, the defendant and his friend tried to borrow money on the day of the robbery.
The fact that witnesses gave inconsistent descriptions of the robber’s mask and the defendant’s costume does not mean that the evidence in this case was insufficient. The jury may reasonably overlook inaccuracies in testimony that are within the range of human error. State v. Cates, 202 Conn. 615, 628 n.4, 522 A.2d 788 (1987). “Whether there seems to be contradiction between different witnesses or confusion in the testimony, it is precisely this type of factual conflict that Anglo-American jurisprudence has traditionally entrusted to the jury.” State v. Gaynor, supra, 504; State v. Moore, 3 Conn. App. 503, 504, 489 A.2d 1069 (1985); State v. Nelson, 38 Conn. Sup. 374, 376, 448 A.2d 219 (1982). The store clerk and her husband testified that the robber wore a clown mask, bald on top with red hair on the sides. Another witness stated that she saw the defendant at a party one month before the robbery with a costume, which she described as an old man’s hat with red hair sticking out. Given that each description contained the distinct feature of red hair, the jury could reasonably have overlooked other inconsistent aspects of the descriptions.
Viewing the evidence in the light most favorable to sustaining the verdict, we conclude that there was suf*305ficient evidence for the jury to conclude beyond a reasonable doubt that the defendant participated in the robbery.
II
The defendant’s second claim is that the court erred in denying his motion for judgment of acquittal because the evidence was insufficient to prove that the pellet gun used in the robbery was a dangerous instrument, as defined in General Statutes § 53a-3 (7).1 This claim relates only to the defendant’s conviction on the first count of first degree robbery in violation of General Statutes § 53a-134 (a) (3). In denying the defendant’s motion for judgment of acquittal on the first count, the trial court reasoned that, although the state did not prove that the pellet pistol was loaded at the time of the robbery, the conviction could be sustained on the ground that the pellet pistol was a dangerous instrument because it could have been used as a bludgeon. This reasoning was erroneous, however, because all of the evidence adduced at trial showed that the defendant did not threaten to bludgeon the victims, although he did threaten to shoot them.
Because there was no evidence that the defendant threatened to use the pistol as a bludgeon, the verdict on the first count can be sustained only on the assump*306tion that an unloaded pellet pistol is a dangerous instrument under § 53a-134 (a) (3). In this regard, it is important to understand the origin of the distinction made in the penal code between deadly weapons and dangerous instruments. Under prior law, weapons were distinguished based on whether they were designed to do violence. A weapon designed for the sole purpose of doing violence was considered deadly per se (by or through itself). The law recognized that ordinary objects, not designed or manufactured for violence, could also be deadly, depending on the actual manner in which they are used. Thus, ordinary objects could be considered deadly weapons under the law, even though they are not deadly per se. See State v. Litman, 106 Conn. 345, 352-53, 138 A. 132 (1927).
Our modern penal code preserves, to a great extent, the distinction between those weapons that are deadly per se and those that are not.2 General Statutes § 53a-3 (6) defines “deadly weapon” and § 53a-3 (7) defines “dangerous instrument.” The term deadly weapon is confined to those items designed for violence. The concept of a dangerous instrument, on the other hand, focuses on the manner in which an object is used or attempted or threatened to be used, and its capabilities under these circumstances. See Commission to Revise the Criminal Statutes, 1971 comments, p. 3.
*307The fact that the legislature intended the term dangerous instrument to apply only to those weapons that are not deadly per se is reflected in our case law. The cases interpreting the term dangerous instrument all involve ordinary objects that are actually used or threatened to be used in ways that would likely cause death or serious physical injury. State v. Killenger, 193 Conn. 48, 54, 475 A.2d 276 (1984) (hammer or flashlight); State v. Grant, 177 Conn. 140, 411 A.2d 917 (1979) (tire iron); State v. Jones, 173 Conn. 91, 376 A.2d 1077 (1977) (hockey stick); State v. Vuley, 15 Conn. App. 586, 545 A.2d 1157 (1988) (pipe); State v. Ortiz, 14 Conn. App. 493, 504, 542 A.2d 734 (1988) (stick); State v. Frazier, 7 Conn. App. 27, 39-40, 507 A.2d 509 (1986) (key); State v. Levine, 39 Conn. Sup. 494, 497-98, 466 A.2d 814 (1983) (garden hose).
Under § 53a-134 (a) (3), the state had the burden of showing that, under the circumstances in which the pellet pistol was used, it was actually capable of causing death or serious physical injury. State v. Grant, supra, 146 n.5. The defendant threatened to shoot the store clerk, but did not threaten to bludgeon her. Under these circumstances, an unloaded pellet pistol is not a dangerous instrument. Because the state failed to prove that the pistol was loaded during the robbery, there is error as to the first count in the trial court’s denial of a judgment of acquittal.3
*308The evidence was sufficient, however, to sustain a conviction for third degree robbery, in violation of General Statutes § 53a-133. Third degree robbery is a lesser offense included in the crime of first degree robbery. See State v. Whistnant, 179 Conn. 576, 588, 427 A.2d 414 (1980). Under Practice Book § 899, if the judicial authority directs an acquittal for the offense specified in the verdict, but not for a lesser included offense, he or she may modify the verdict accordingly. On the basis of the charging documents, we find that the defendant had sufficient notice that he would be exposed to possible conviction on the lesser included offense of third degree robbery in the first count. State v. Jacobowitz, 182 Conn. 585, 591, 438 A.2d 792 (1981); State v. Hudson, 14 Conn. App. 472, 476-77, 541 A.2d 539 (1988). The state requested and received a jury instruction on the lesser included offense in the first count. We conclude that the jurors would necessarily have found the defendant guilty of the lesser charge, had they considered it. See State v. Aleksiewicz, 20 Conn. App. 643, 650-51, 569 A.2d 567 (1990).
Ill
The defendant next claims that the trial court erred in denying his motion for judgment of acquittal on the second count for the charge of conspiracy to commit first degree robbery.4 “ ‘The commission of the substantive offense and a conspiracy to commit it are separate and distinct crimes.’ ” In re Luis R., 204 Conn. 630, 637, 528 A.2d 1146 (1987). “ ‘ “To establish the crime of conspiracy under Section 53a-48 of the Gen*309eral Statutes, the state must show that there was an agreement between two or more persons to engage in conduct constituting a crime and that the agreement was followed by an overt act in furtherance of the conspiracy by any one of the conspirators.” . . .’ ” (Citations omitted.) State v. Rouleau, 204 Conn. 240, 258, 528 A.2d 343 (1987). Conspiracy is a crime of the same grade and degree as the most serious offense that is the object of the conspiracy. General Statutes § 53a-51. On appeal, this court construes the evidence “in the manner most favorable to sustaining the verdict.” State v. Gunning, 183 Conn. 299, 309, 439 A.2d 339 (1981).
The uncontroverted evidence that the second robber wielded a tire iron sufficed to support the jury’s conclusion that the two robbers conspired to commit first degree robbery. See State v. Ghere, 201 Conn. 289, 299-300, 513 A.2d 1226 (1986). Under the circumstances, the tire iron clearly was a dangerous instrument under General Statutes § 53a-134 (a) (3). See State v. Grant, supra.
The defendant argues that the conviction for conspiracy to commit first degree robbery cannot stand because the state amended the long form information before submitting it to the jury and because the court did not recount all the elements of first degree robbery when instructing the jury on the second count. We find these claims to be without merit.
The information originally charged the defendant in the second count with conspiracy to commit “robbery in the first degree” in violation of General Statutes §§ 53a-48 and 53a-134 (a) (3). The second count was subsequently amended pursuant to Practice Book § 624 to charge the defendant with conspiracy to commit “robbery.” The reference to § 53a-134 (a) (3) was not changed.
*310An information can be amended under Practice Book § 624 only to charge the defendant with the same crime as in the original information or with a lesser included offense. State v. Jacobowitz, supra, 590. The state contends that the information was amended to charge the defendant with the same offense, while the defendant argues that the state could have meant only to reduce the charge to the lesser included offense of conspiracy to commit third degree robbery.
The sixth amendment to the United States constitution provides in part: “In all criminal prosecutions, the accused shall enjoy the right ... to be informed of the nature and cause of the accusation.” This provision is implemented by Practice Book § 618, which governs the form of information to be used in felony cases. Section 618 provides in part that “[t]he information shall state for each count the official or customary citation of the statute, rule, regulation, or other provision of law which the defendant is alleged to have violated.” “Under our practice, it is sufficient for the state to set out in the information the statutory name of the crime with which the defendant is charged, leaving to the defendant the burden of requesting a bill of particulars more precisely defining the manner in which the defendant committed the offense. Practice Book §§ 495, 498; State v. Davis, 141 Conn. 319, 106 A.2d 159 [1954]; see State v. Brown, 163 Conn. 52, 61, 301 A.2d 547 [1972]. Once such a bill of particulars has been filed or where . . . the information is sufficiently precise that no bill of particulars is needed, the state is limited to proving that the defendant has committed the offense in substantially the manner described. State v. Beaulieu, 164 Conn. 620, 625, 325 A.2d 263 [1973]; State v. DiLorenzo, 138 Conn. 281, 284-85, 83 A.2d 479 [1951]; State v. Scott, 80 Conn. 317, 321, 68 A. 258 [1907]; cf. State v. Cari, 163 Conn. 174, 183-84, 303 A.2d 7 [1972]. In the event the state offers evidence *311to prove that the defendant committed an offense in a manner other than that set out in the information and bill of particulars, the trial court may grant the state an amendment to conform the evidence to the information, but must ensure that no prejudice to the defendant results. See State v. Rafanello, 151 Conn. 453, 456, 199 A.2d 13 [1964]; see also Practice Book § 525.” State v. Ruiz, 171 Conn. 264, 270, 368 A.2d 222 (1976).
The argument of the defendant that the effect of the amendment of the information was to reduce the charge in the second count to conspiracy to commit third degree robbery fails because the state did not change the reference to General Statutes § 53a-134 (a) (3) in that count.5 Upon the information that the jurors saw, the defendant was charged with conspiracy to commit robbery in violation of General Statutes §§ 53a-48 and 53a-134 (a) (3). They returned their verdict accordingly.
The defendant also contends that the trial court’s charge to the jury on the second count was inadequate to apprise the jurors of all of the elements of conspiracy to commit first degree robbery. According to the defendant, the jurors were unaware that the threatened use of a dangerous instrument is an aggravating factor that distinguishes the crime of conspiracy to commit first degree robbery from the offense of conspiracy to commit third degree robbery because the court made no mention of the dangerous instrument element in its charge to the jury on the second count. The defendant concludes that the jury could not have convicted the defendant of a greater offense than conspiracy to commit third degree robbery because it cannot convict an *312accused “without even knowing what are the essential elements of the crime charged.” State v. Griffin, 175 Conn. 155, 162-63, 397 A.2d 89 (1978).
The defendant did not take an exception to the charge to the jury and so we must determine whether to review this claim under the guidelines recently articulated in State v. Golding, 213 Conn. 233, 239-42, 567 A.2d 823 (1989). In the present case, the defendant has presented arguments that, if correct, would lead to the conclusion that there was a violation of a fundamental constitutional right that clearly deprived the defendant of a fair trial. See id., 241. Moreover, we are persuaded that if the defendant is correct, then the constitutional violation would not be subject to harmless error analysis. We, therefore, address the merits of the claim to determine whether the alleged constitutional violation clearly exists.
“ ‘ “ ‘The test to be applied to any part of a charge is whether the chargé considered as a whole presents the case to the jury so that no injustice will result.’ State v. Mullings, 166 Conn. 268, 275, 348 A.2d 645 [1974]; Siladi v. McNamara, 164 Conn. 510, 515, 325 A.2d 277 [1973].” State v. Roy, 173 Conn. 35, 40, 376 A.2d 391 (1977). State v. Stepney, 191 Conn. 233, 247, 464 A.2d 758 (1983), cert. denied, 465 U.S. 1084, 104 S. Ct. 1455, 79 L. Ed. 2d 722, reh. denied, 446 U.S. 954, 104 S. Ct. 2163, 80 L. Ed. 2d 547 (1984). It is well established that jury instructions must be read as a whole and that individual instructions are not to be judged in ‘artificial isolation’ from the overall charge. Cupp v. Naughten, 414 U.S. 141, 147, 94 S. Ct. 396, 38 L. Ed. 2d 368 (1973); State v. Holmquist, 173 Conn. 140, 151, 376 A.2d 1111, cert. denied, 434 U.S. 906, 98 S. Ct. 306, 54 L. Ed. 2d 193 (1977). Although the Cupp court stated, ‘a single instruction to a jury may not be judged in artificial isolation, but must be viewed in the context of the overall charge,’ that court also recognized that that ‘does *313not mean that an instruction by itself may never rise to the level of constitutional error . . . .’ Cupp v. Naughtm, supra, 146-47; see Cool v. United States, 409 U.S. 100, 93 S. Ct. 354, 34 L. Ed. 2d 335 (1972). The due process clause ‘protects the accused against conviction except upon proof [by the state] beyond a reasonable doubt of every fact necessary to constitute the crime with which he is charged.’ In re Winship, 397 U.S. 358, 364, 90 S. Ct. 1068, 25 L. Ed. 2d 368 (1970); accord Patterson v. New York, 432 U.S. 197, 210, 97 S. Ct. 2319, 53 L. Ed. 2d 281 (1977). . . . [T]he defendant has a constitutional right to have the jury adequately instructed in order to guarantee him a fair trial. Moreover, this right directly implicates the requirement of correct instructions on the standard of proof as well as the burden of proof. A misstatement of the law is more likely to be prejudicial than an omission or incomplete instruction. Henderson v. Kibbe, 431 U.S. 145, 155, 97 S. Ct. 1730, 52 L. Ed. 2d 203 (1977); State v. Kurvin, 186 Conn. 555, 563, 442 A.2d 1327 (1982); see State v. Preyer, 198 Conn. 190, 198-99, 502 A.2d 858 (1985).” State v. Rouleau, supra, 251-53.
In light of the trial court’s entire charge, the argument of the defendant that the jury was not apprised of all of the elements of conspiracy to commit first degree robbery is without merit. In explaining the charges against the defendant contained in the information, the court stated that the defendant was charged in the second count with conspiracy to commit first degree robbery in violation of General Statutes §§ 53a-48 and 53a-134 (a) (3). In its instructions on the first count, the court explained the elements of first degree robbery. The court also gave an instruction on the lesser included offense of third degree robbery, as requested by the state. The court then explained the elements of the crime of conspiracy in its instructions on the second count. The charge as a *314whole was sufficient to apprise the jury of all of the elements of conspiracy to commit first degree robbery, and there was nothing in the court’s instructions to suggest that the defendant should not be found guilty of conspiracy to commit first degree robbery.
There is error in part; the judgment is set aside as to the first count only and the case is remanded with direction to render judgment of guilty of robbery in the third degree on that first count, and to resentence the defendant accordingly.
In this opinion Spallone, J., concurred.
The jury’s verdict on the first count cannot be sustained on the ground that another participant in the robbery threatened the use of a dangerous instrument. See General Statutes § 53a-134 (a) (3). This is true despite the fact that the store clerk’s husband testified at trial that the second robber threatened him with a tire iron. The long form information charges only that the defendant personally threatened the use of a dangerous instrument and does not also charge that he participated in a robbery in which another participant threatened the use of a dangerous instrument. “[T]he state is limited to proving that the defendant has committed the offense in substantially the manner described.” State v. Belton, 190 Conn. 496, 501, 461 A.2d 973 (1983); quoting State v. Ruiz, 171 Conn. 264, 270, 368 A.2d 222 (1976).
Under General Statutes § 53a-3 (6), firearms are deadly per se, whether loaded or unloaded. This provision expressly exempts §§ 29-38 and 53-206 from its coverage. The latter two statutes apply to carrying firearms on one’s person or in one’s motor vehicle. Unloaded firearms are not deadly per se under those statutes. State v. Scully, 195 Conn. 668, 677, 490 A.2d 984 (1985). The reason for these exemptions is that “the unloaded rifle or shotgun cannot be deemed per se ‘deadly weapons’ when transported in a motor vehicle; otherwise, even those with legitimate reasons for possessing an unloaded firearm in a motor vehicle, e.g., a hunter, would fall within the sweep of those provisions.” Id., 678 n.13. Outside of these two statutory exemptions, however, unloaded firearms are per se deadly, and this conforms with prior law. See State v. Reed, 157 Conn. 464, 468, 254 A.2d 449 (1969).
The defendant in the present case could have been charged with first degree robbery under either General Statutes § 53a-134 (a) (2) or § 53a-134 (a) (4). The pellet pistol used in the robbery is a weapon designed for violence. The weapon fits the definition of the term “deadly weapon” at § 53a-3 (6). This term appears in § 53a-134 (a) (2). The weapon also fits the definition of “firearm” in § 53a-3 (19). This term appears in § 53a-134 (a) (4). If the defendant had been charged under either of these sections, the state would not have had to prove that the pistol was loaded at the time of the robbery. The only issue would have been whether the weapon was operable. See State v. Hawthorne, 175 Conn. 569, 572, 402 A.2d 759 (1978); State v. Aleksiewicz, 20 Conn. App. 643, 569 A.2d 567 (1990). The fact that the state may well have offered evidence sufficient *308to warrant a conviction for first degree robbery under either of the two sections is immaterial, however, because the defendant was not charged under those sections. State v. Palkimas, 153 Conn. 555, 563, 219 A.2d 220 (1966); State v. Kristy, 11 Conn. App. 473, 481, 528 A.2d 390, cert. denied, 206 Conn. 801, 535 A.2d 1315 (1987).
One ground upon which this claim is based is that there was, according to the defense, insufficient evidence to identify the defendant as a participant in the robbery. We have already held that the evidence was sufficient.
On August 6,1986, the defendant motioned for a bill of particulars. That motion does not appear in the appellate record. Nor is there any indication whether the motion was granted or denied. “It is the responsibility of the appellant to provide an adequate record for review.” Practice Book § 4061.