The content of an application must not be considered to be a reservoir from which features pertaining to separate embodiments of the application could be combined in order to artificially create a particular embodiment (T 296/96 ; T 1206/01 ; T 3/06, and more recently see e.g. T 1239/08 and T 1648/11).
In T 770/90 the board ruled that an unduly broad claim not supported by the description as originally filed was not a suitable "reservoir" for amendments. On the issue of Art. 123(2) EPC 1973, the board stated in T 296/96 that the content of a document was not to be viewed as a reservoir from which features pertaining to separate embodiments could be combined in order to artificially create a particular embodiment. When assessing whether a feature had been disclosed in a document, the relevant question was whether a skilled person would seriously contemplate combining the different features cited in that document. That was not the case in the application as filed.
In the context of Art. 123(2) EPC the original drawings cannot be considered as a reservoir of features on which the applicant or a patent proprietor can draw when amending the claims (T 1120/05, see below point 1.5).