Revelation 9:15

And the four angels were made free, who were ready for the hour and day and month and year, that they might put to death a third part of men.

Revelation 8:7

And at the sounding of the first, a rain of ice and fire, mixed with blood, was sent on the earth: and a third part of the earth, and of the trees, and all green grass was burned up.

Revelation 9:18

By these evils a third part of men was put to death, by the fire, and the smoke, and the burning smell which came out of their mouths.

Revelation 8:9

And destruction came on a third part of the living things which were in the sea, and on a third part of the ships.

Revelation 8:11-12

And the name of the star is Wormwood: and a third part of the waters became bitter; and a number of men came to their end because of the waters, for they were made bitter.

Revelation 9:5

And orders were given them not to put them to death, but to give them great pain for five months: and their pain was as the pain from the wound of a scorpion.

Revelation 9:10

And they have pointed tails like scorpions; and in their tails is their power to give men wounds for five months.

Treasury of Scripture Knowledge

Summary

And the four angels were loosed, which were prepared for an hour, and a day, and a month, and a year, for to slay the third part of men.

An hour

Bible References

An hour

Revelation 9:5
And orders were given them not to put them to death, but to give them great pain for five months: and their pain was as the pain from the wound of a scorpion.

For to

Revelation 9:18
By these evils a third part of men was put to death, by the fire, and the smoke, and the burning smell which came out of their mouths.
Revelation 8:7
And at the sounding of the first, a rain of ice and fire, mixed with blood, was sent on the earth: and a third part of the earth, and of the trees, and all green grass was burned up.

Basic English, produced by Mr C. K. Ogden of the Orthological Institute - public domain