emorandum error. <A _ document alleging error in fact, accompanied by an affidavit of such matter of fact.—Memorandum of alteration. Formerly, in England, where a patent was granted for two inventions, one of which was not new or not useful, the whole patent was bad, and the same rule applied when a material part of a patent for a single invention had either of those defects,

2 . an . : sed ,