How do I get into the warehouse at the docks?

Hint 1 of 13:

You'll have to satisfy Watson by looking through the window.

Hint 2 of 13:

But the window is too dirty to do you any good right now.

Hint 3 of 13:

Did you notice the pail above the door?  If you could reach it, you might be
able to clean the window.

Hint 4 of 13:

You need to climb something.

Hint 5 of 13:

Push the crate and stand on it.