A comparison of Comet Holmes imaged with a high quality APO refractor and CCD camera on November 18, 2007 from Mount Wilson Observatory versus a photograph taken by famed astronomer E. E. Barnard on December 8, 1892 from the Lick Observatory in Northern California with a 6" portrait lens camera.

By examining the two images it's obvoius that the current apparition of Comet Holmes (2007) has a very similar "outburst" shape to what it did nearly 115 years ago when Edward Emerson Barnard photographed it from Lick. The two shots were taken at different image scales so you can't compare them directly for size. In the 2007 image the comet has an apparent size of 30 arc-minutes while it has a 25 arc-minute size in the historic 1892 photo.