I have a big black spider who makes webs all over my rain gutters. (is this a US term? the horizontal part of the downspouts, is what I mean)

The spiders seem to live in the expansion joints between the bricks and they are BIG and BLACK and CREEPY! Yuck!

I was told to "spray them" but we don't spray so I just remove their webs weekly and spray the spiders with a hose! Yuck!

Now I just found one curled up cozy in a towel in the house. It was really hard to squish, too. Yuck!

What are they? Are they dangerous?

(as a side note, I notice the cute little sparrows will fly along and pick flies out of the spider webs along the gutters!! They are so clever to "shop" for bugs that way--and they do it all day if I don't go remove the webs)