The yarn number is the length in yards of one pound of the yarn, divided by 1600. Symbol Nar. This is the same as the weight in ounces of 100 yards. So one pound of number 1 run yarn is 1600 yards long, one pound of number 2 run yarn is 3200 yards long, and so on.
As with most other volcanoes in the Cascade Range, Mount St. Helens is a large eruptive cone consisting of lava rock interlayered with ash, pumice, and other deposits. The mountain includes layers of basalt and andesite through which several domes of dacite lava have erupted.
On May 18, 1980 a major volcanic eruption occurred at Mount St. Helens, a volcano located in the state of Washington, United States.ount St. Helens remained dormant from its last period of activity in the 1840s and 1850s until March 1980. Several small earthquakes, apparently beginning on March 15, indicated that magma may have begun moving below the volcano.