quarter plate: a photographic plate measuring 3.25 inches by 4.25 inches
plate: a flat sheet of metal or glass on which a photographic image can be recorded
alzheimer's disease: a progressive form of presenile dementia that is similar to senile dementia except that it usually starts in the 40s or 50s; first symptoms are impaired memory which is followed by impaired thought and speech and finally complete helplessness