If you ever doubted that Revelation was John on acid, I'm about to prove it to you. Revelation 14:17-20 is about a winepress. Except it isn't pressing grapes, really.
17 Another angel came out of the temple in heaven, and he too had a sharp sickle. 18 Still another angel, who had charge of the fire, came from the altar and called in a loud voice to him who had the sharp sickle, “Take your sharp sickle and gather the clusters of grapes from the earth’s vine, because its grapes are ripe.” 19 The angel swung his sickle on the earth, gathered its grapes and threw them into the great winepress of God’s wrath. 20 They were trampled in the winepress outside the city, and blood flowed out of the press, rising as high as the horses’ bridles for a distance of 1,600 stadia.That's a lot of blood. How much blood? Let's find out! One stades, in Rome at the time, is about 0.92 furlongs; a furlong is an eighth of a modern mile. So 1600 stadia was 200 Roman miles, but it works out to 183.93 modern miles. I'm going to interpret here, and say that when the blood flowed out for a distance of 1600 stadia, that means the distance the blood went out from the winepress John saw, i.e. that they're talking about the radius of the lake of blood. So we've got the radius of our cylinder (approximating here, of course, that the lake is circular and the depth is constant throughout); now we need the height in order to calculate the volume. Unfortunately, "as high as the horses' bridles" isn't an accurate measurement, but the bridle of a horse is typically between four and six feet from the ground. Call it 5 feet for simplicity.
So, we've got the height of our cylinder in feet. The radius, in feet so our units match, is 183.93 * 5280 = 971,150.4 feet. Now, we go ask a European high school student what the formula is for the volume of a cylinder, and we find out that it is pi * the radius squared * the height. So, pi * 971150.4^2 * 5 = 1.481470008 x 10^13 cubic feet. There are 28.3168466 liters in a cubic foot, giving us 4.195055897 x 10^14 liters of blood.
Now, let's turn this into people. I think we can safely assume that the winepress is only squeezing out blood; it is after all a divine winepress, so it should be able to discriminate. The human body contains approximately 5 liters of blood, so we can divide our total volume of blood by 5, and get 83,901,117,930,000 crushed