Common Sense

Today I found this on the tracks near my house. I have no clue what it is except that it is a brick and it has text on it reading"NO 1 WOODBRIDGE NJ". There is also some writing on it above the rest of the text. It was sticking into the hill on the right side of the tracks. What is it and how did it get from NJ to Allentown PA? If anyone knows please contact me at paoutdoorjournal@gmail.com