Bifrost

It is as substanceless as shimmering vapor, yet as solid as adamantine-forged glass, but if one doubts for an instant while on footfall in appraise of its substanceless-seeming, one shall slip through and fall the chasm-long. It cannot be walked by those who know only one way of being or doing. Its rainbow starshine is the union of spectral spread into thickest steel support for those with faith in airy ways. It is a great tester of faith that fails the faltering and tries the mind's eye to see in diverse color.