What was the greatest spur to American settlement of California
{"Image DocumentName": "What was the greatest spur to American settlement of California?", "Image ImageDescription": "Beaver trapping. gold rush. missionaries. cheap land.", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}