Evolution and Revolution in Microscopy - I

Extract

Disney, Hill and Baker in their 1928 booh on the Origin and Development of the Microscope, quote the 1829 article on Optics of the London Encyclopedia as saying; “Microscopes, though but toys compared with telescopes, nevertheless deserve to be rendered as perfect as possible; for they yield not to them in the quantity and variety of rational amusement which they are capable of introducing to us (though not of the sublime description of the wonders of the heavens). Compound microscopes, though not so much to be depended upon for the purposes of discovery and philosophical investigation as single lenses, are still the best adapted for recreation”. It is hard to imagine that this was written at about the time when Robert Brown of motion fame, was discovering the celt nucleus (1831), the repository of the genetic code and thus arguably laying the foundations for all of modern biology. The sentence quoted might be taken to suggest that there was no evolutionary connection between hand lenses and compound microscopes, since as late as the 1830s the two still competed.

In trying to follow the evolution of microscopes it is trite to state that lenses had to come first. It was known for a long time that objects seen through a glass bulb full of water appeared enlarged, but the water was thought the important factor and it was not until the time of Alhazen (962-1038) that the action of a lens was understood. Roger Bacon (1242-1292) wrote “if one looks at letters and other minute things though the medium of a crystal or glass or other lens put over the letters... he will see the letters much better and they will appear much larger to him... and therefore this instrument is useful to old men and to those having feeble sight” Spectacles seem to have been invented by Salvano d'Aramento degli Arrtati of Florence who died in 1317, the secret process of how to make them being revealed by a contemporary, Alessandro della Spina of Pisa. The use of lenses in visualizing small objects made slow progress at first but eventually led to “macroscopy”, in the form of spectacles and then to microscopy.