How to Find a Spike in Manhattan

There have been a bunch of rumors of other ones that have been found on Manhattan. And from my vague research, there are two that are plausibly could be the original. So I thought I would solve just problem by looking at the grid and working out with the middle of the grid. Now here's our issue. First street starts way up the island. You've already got all the other rows underneath it. directly below first is a street that looks like it's called Houston. It's not. The exact middle is real close and side to side. Instead of being between 4th and 5th Avenue instead of being between 6th and 7th. Okay so now we need to know