In Austin v. Director of Patuxent Institution, 245 Md. 206, 225 A.2d 466 (1967), the issue there was whether the circuit court had exceeded its authority under Md. Code (1957), Article 31B, section 5, by granting the State's motion for a new trial after a jury found that Austin was not a "defective delinquent." The Court noted that, although the circuit court is a court of general jurisdiction, it becomes a court of special jurisdiction in defective delinquent proceedings. The court's authority in such proceedings, therefore, is limited to the authority conferred upon it by Article 31B. In explaining the difference between courts of general and special jurisdiction, the Court stated: A court can be a court of general jurisdiction for some purposes and a court of limited jurisdiction for other purposes . When therefore a court of general jurisdiction proceeds under a special statute it becomes a court of limited jurisdiction for the purpose of such proceeding. See 21 C.J.S. Courts 2. Accordingly, where a court of general jurisdiction undertakes to carry out a special power, a decision made in the exercise of such power is treated as a ruling of a court of limited jurisdiction and the presumption, applicable to a court of general jurisdiction, that it acted within the scope of its jurisdiction does not apply. See 20 Am. Jur. 2d, Courts 103. (245 Md. at 209.) Although it discussed the difference between courts of general and special jurisdiction, the Court's holding was not based upon whether a presumption of jurisdiction existed, but rather upon the scope of a court's authority when proceeding under a special statute. The Court determined that, when the circuit court was ruling on the status of a defendant alleged to be a defective delinquent, it was a court of special jurisdiction exercising a special statutory power. The Court held that the circuit court erred by granting the motion for a new trial. It noted that the power to grant such a motion, although within the inherent power of the circuit court as a court of general jurisdiction, is not within the power of a circuit court with special jurisdiction. Because the authority to grant a new trial was not given to the court by Article 31B, the court lacked the authority to do so.