Salicine Crystals photographed under a microscope
This colourful illustration is a polarised light photomicrograph of a most interesting chemical called Salicine. In other words it is a highly magnified image (enlarged about two hundred times) taken with the aid of a special microscope technique that uses the natural refraction of these crystals to produce a pattern of rainbow colours.
The same lighting technique works on any mildly refractive medium. In the above case this is a tiny mat woven from a single strand of hair from the tail of a white horse. Notice the knot and imagine how difficult this must have been; the original glass microscope slide was made over a hundred years ago!
You'd never guess... this is a cross-section through a human tooth. No dye colouration or digital camera tricks are involved the colours come solely from the polarised light source that has passed through a selenite crystal and thereby become dichroic.
Below is a water flea... Daphnia pulex. The colours are due to dichroic polarised light. Daphnia give birth by parthenogenesis during the summer; three daughters can be seen inside her carapace. Males only come along when the going gets tough... overwinter.
This is the radular of a marine snail. The whelk uses this wood-rasp like tongue to scrape its dinner off the rocks.
These are fish scales from a dover sole, arranged by a very patient Victorian microscopist.
