As an update, I ordered a second shield from spark fun (RS232 Shield - DEV-11958 - SparkFun Electronics), but am still unsuccessful in establishing communications with my DEC Writer. For each RS-232 shield, I can see an LED blink very few seconds when I execute a sketch to print to serial1 with a delay loop. I now see a new blog from Sergey on configuring UART which differs a bit from the script suggested previously so I will his procedure that next!
Intel Galileo - Configuring the Serial Port in Linux - Malinov Family Web Presence