Lungscapes

The invention of an instrument called the OPTICAL MICROSCOPE and the new possibilities it offered to observe living material must be considered a major milestone in the advance of our understanding of the mechanisms of life. Huge numbers of important observations have been made using this instrument, but unfortunately it only produces twodimensional images. The advent of the ELECTRON MICROSCOPE - first the TRANSMISSION ELECTRON MICROSCOPE (TEM) and then the SCANNING ELECTRON MICROSCOPE (SEM) made it possible to observe the three-dimensional structure of specimen, literally adding a whole new dimension to our understanding and bringing about a second major milestone in microscopy. With their highly specific architecture and great functional significance, the respiratory apparatus and the airways have received particluar atttention, and extensive series of investigations with SEM have been done.