Meet me at the Sears Tower. Bring a mouse.

Indeed, sufficiently small animals cannot be hurt in a fall from any height: A monkey is too big, a squirrel is on the edge, but a mouse is completely safe. The mouse-sized people in Dr. Cyclops could have leapt off the tabletop with a cry of "Geronimo!" secure in the knowledge that they were too small to be hurt. |Source|

Addendum: So I suppose that the mouse business is common knowledge. But what about this?:

However, before pulling the bridge down, the monster extends his tentacles about halfway up the support towers. The top of the support towers stand 500 feet above the deck, itself 220 feet above the high-water mark. At one atmosphere for every 33 feet and an elevation of 470 feet, that's a total pressure of about 14 atmospheres (209 pounds per square inch). For the first time in its life, there was no surrounding mass of water to offset the pressure increase and the full load of this pressure would act to distend its arteries.

The evidence clearly points to the poor cephalopod suffering a sudden and massive cerebral hemorrhage from this excess pressure just as it rips down the Golden Gate Bridge. The subsequent passivity of the giant octopus now makes perfect sense--its higher faculties were gone and the only responses it made were due to peripheral reflexes, grabbing the submarine in response to tactile stimulation, twitching when hit with the diver's spear. |Ibid.|

He's talking about It Came from Beneath the Sea. Obviously.