Multiple specimen holders make it possible to examine several (up to 7) specimens by SEM without the need to vent the microscope, replace the specimen, and evacuate the microscope again. Using such a holder in a Philips XL-30 ESEM frequently showed zigzagged outlines of bacteria obtained at magnifications higher than 10,000x. The zigzag outlines were not associated with charging artifacts as the filter edges were painted with a silver-based cement prior to gold coating. The severity of the zigzag lines varied from day to day. Sometimes they were barely noticeable whereas at other times they developed during a half-day session.