Those are really killer transistors....1700V! But overkill for this application. And a transistor rated for that voltage won't have as good current gain as a lower-voltage transistor. Indeed the datasheet suggests the current gain is only about 8 at Ic=1A meaning you'd need 125mA out of the Arduino pin to get 1A of motor current.
You'd be better off with a MOSFET or a higher-gain BJT. And driving a BJT base without a resistor is a bad idea as you may damage your Arduino. There really isn't anything to limit the current out of the I/O pin.
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The Gadget Shield: accelerometer, RGB LED, IR transmit/receive, speaker, microphone, light sensor, potentiometer, pushbuttons