And as the years went by, animals delivered letters by the thousands.

5 seconds sound clip from the Santa Claus Is Comin' to Town (1970) movie soundboard.

You can hear this line at 00:45:04.798 in the Blu-ray version of the movie.

Quote context

[...]

- We'll build ourselves a nice house. Heck, while we're at it, we'll build ourselves a castle, and the best toy factory in the world.

- And that's just what they did. And in no time at all...

- Santa's castle and workshop!

- Up at the North Pole.

- Well, as soon as the buildings were built, they settled in and started making toys in earnest. Oh, they needed toys.

- Because you see, despite everything the Meisterburgers tried, the legend of Kris Kringle, or Claus as he now was known just grew and grew.

- And as the years went by, animals delivered letters by the thousands.

- Oh, just look at this list.

- Well, load up the sleigh.

- Ah, this is the fourth trip this month.

- You see, he still had to travel by night because he was considered an outlaw.

[...]