Found it! Here's the text:
14 July, 1937
Dear Jonesy,
I wanted your help on a case I am working on. with Pinkertons: One Casper Gutman, and a slew of other characters, approached me about locating a black bird that they called the Maltese Falcon. I was able to get my hands on the bird only to discover that it was a fake. The lot of them were arrested and sent to prison, only to break out one by one (they should have sent them to the Rock).
Now they are on the trail of the bird again and Lieutenant Dundy has asked for my help in tracking these fugitives down. The only lead I can think of is this dingus. Have you heard of it? Any ideas where it might be? I think the only way to find these hoodlums is to find the bird.
Wire me with what ever information you might have. Thanks, Jones. Next time you’re in San Francisco, look me up. It’s been over two years. I believe you owe me a scotch.
By the way, I thought you might find it ironic that one of the weapons involved with this group was a Webley-Fosbery. That makes two folks I know who carried this ridiculous pistol.
Your friend,
(signed "Sam Spade")
Samuel Spade
EP
