The clips are all very, very short, I think to aid downloading speed, but they're also captioned very well, including interesting annotations like telling you to note the hairstyle of one of the soldiers shown because it was in vogue at the Front in 1916. It's worth a look if you have a fast connection. I viewed the clips in QuickTime.
A long while back, I bought World War I Films of the Silent Era on DVD, which is pretty good. "Made between 1916 and 1917, when much of the world was embroiled in the first Great War, these 3 silent films show the role of cinema as propaganda and news in society. 1916's FIGHTING THE WAR was filmed by American adventurer David C. Thompson, who managed to disguise his identity and capture some amazing footage of the front lines. 1917's THE LOG OF THE U-35 is a visual record of 2 different submarine sinkings. 1917's THE SECRET GAME is a narrative film which tells the story of Japanese and U.S. spies working together to get information. And finally, THE MOVING PICTURE BOYS IN THE GREAT WAR is a latter day documentary which tracks the altering attitudes toward the war within movies like the above."