been pushed too far, she nips back at her master. She cries when he scolds her, and he placates her with a pumpkin. Throughout the act, prehistoric denizens such as a flying lizard continually distract Gertie. She tosses a mammoth in the lake; when it teases her by spraying her with water, she hurls a boulder at it as it swims away. After she quenches her thirst by draining the lake, McCay has her carry him offstage while he bows to the audience. Production Gertie was McCay's first piece of animation with detailed backgrounds. Main production began in mid-1913. Working in his spare time, McCay drew thousands of frames of Gertie on sheets of rice paper, a medium good for drawing as it did not absorb ink, and as it was translucent it was ideal for the laborious retracing of backgrounds, a job that fell to art student neighbor John A. Fitzsimmons. The drawings themselves occupied a area of the paper, marked with registration marks in the corners to reduce jittering of the images when filmed. They were photographed mounted on large pieces of stiff cardboard. McCay was concerned with accurate timing and motion; he timed his own breathing to determine the timing of Gertie's breathing, and included subtle details such as the ground sagging beneath Gertie's great weight. McCay consulted with New York museum staff to ensure the accuracy of Gertie's movements; the staff were unable to help him find out how an extinct animal would stand up from a lying position, so in a scene in which Gertie stood up, McCay had a flying lizard come on screen to draw away viewers' attention. When the drawings were finished, they were photographed at Vitagraph Studios in early 1914. McCay pioneered the "McCay Split System" of animation, in which major poses or positions were drawn first and the intervening frames drawn after. This relieved tedium and improved the timing of the film's actions. McCay was open about the techniques that he developed, and refused to patent his system, reportedly saying, "Any idiot that wants to make a couple of thousand drawings for a hundred feet of film is welcome to join the club." During production of Gertie, he showed the details to a visitor who claimed to be writing an article about animation. The visitor was animator John Randolph Bray, who sued McCay in 1914 after taking advantage of McCay's