Petrography rock was affixed to a microscope slide and then ground so thin that light could be transmitted through mineral grains that otherwise appeared opaque. The position of adjoining grains was not disturbed, thus permitting analysis of rock texture. Thin section petrography became the standard method of rock study. Since textural details contribute greatly to knowledge of the sequence of crystallization of the various mineral constituents in a rock, petrography progressed into petrogenesis and ultimately into petrology. It was in Europe, principally in Germany, that petrography advanced in the last half of the nineteenth century. The macroscopic characters of rocks, those
What Work Is workers, but artists, readers, and academics. Levine's poetry is accessible and moving and is utterly American. The poems in "What Work Is" are more subtle in their thematic construction. Levine does not use caricatures in these poems but instead intimates real blue-collar workers. Many of the poems give a representation of a station of life not common in the subject matter of contemporary American poetry. Although not all of "What Work Is" is primarily about the working class. Instead the poems have a wide range and variety. However many of these poems, despite their subject matter, show elements that identify