Probably Thomas Scheidl from Vienna. His maker's mark is usually in an oval, and there is one illustrated in the MAK listing with "indented" sides. The one mark with the "pointed" frame (which differs from the other mark you have posted) is unusual, though. The date (if I make it out correctly) of 1849 would correspond with Th. Scheidl's period of production, however.
Perhaps someone else can clarify the unusual mark.