There must have been some magic in that old silk hat they found, for when they placed it on his head he began to dance around.

15 seconds sound clip from the Rudolph and Frosty: Christmas in July movie soundboard.

You can hear this line at 01:17:19 in the Blu-ray version of the movie.

Quote context

[...]

- He does have something. I dunno. He might have something. Why not ask the genie?

- Frosty the Snowman has his own magic which could prove quite valuable.

- Really? Tell me, what is it?

- His hat.

- Let me show you, o master.

- Frosty the Snowman was a jolly happy soul with a corncob pipe and a button nose, and two eyes made out of coal.

- Frosty the Snowman is a fairy tale they say. He was made of snow but the children know How he came to life one day.

- There must have been some magic in that old silk hat they found, for when they placed it on his head he began to dance around.

- Oh, Frosty the Snowman was alive as he could be, and the children say he could laugh and play just the same as you and me.

- Just think, if you had that hat, and could find the secret of its magic, you could duplicate it over and over again, o master.

- Why, you could bring an army of snowmen to life.

- And Frosty, the only one who knows the true secret of Rudolph's nose, would be lifeless.

- Yes, and I would be safe.

[...]