8 Microbes and You 



By accident, or by logic, it was discovered that if a single 

 ground lens could make things look larger, an object could be 

 magnified still further by using two or more lenses set up in a 

 definite relationship to each other. This compounding of lenses 

 is usually credited to a spectacle maker in Holland in the year 

 1590. Considerable disagreement exists as to the exact name of 

 this individual and as to the spelling of his name. Many books call 

 him Janssen; other histories say his name was Zacharius (miscalled 

 Jansen), the son of John, the spectacle maker. Other books refer 

 to these persons as Hans Jansen and his son Zacharius, with the 

 latter person being the discoverer of the principle of the telescope- 

 two lenses in a tube. The earliest compound microscope was pro- 

 vided with a concave ocular and convex objective. Practical uses 

 of compound lenses were not put to serious use in biological science 

 until the middle of the seventeenth century by Robert Hooke 

 (1635-1723), Antony van Leeuwenhoek (1635^1703), Marcello 

 Malpighi (1628-1694), and others of whom more shall be written 

 later. 



One of the earliest reports on the existence of microorganisms 

 can be found in the writings of an Austrian Jesuit priest, Athanasius 

 Kircher (1601-1680), who reported on the cause of plague as seen 

 in blood of infected individuals. Since his microscopes were ex- 

 tremely crude affairs and his lenses had magnifying limits of only 

 about 32 diameters, it is quite doubtful that Kircher actually saw 

 the organisms we attribute today as the etiologv of this scourge. 

 Kircher was trained in physics, medicine, mathematics, and music, 

 and in 1658 he published a treatise on medical microscopy. 



The name of Galilei Galileo (1564-1642) should not be passed 

 over without at least a mention of his work on lenses. Some 

 historians go so far as to credit this man with the discoveiy of the 

 compound microscope, but because Galileo failed to leave complete 

 records of his work and his findings, other individuals who had 

 left such reports were credited with manv discoveries which might 

 originally have stemmed from the brain of Galileo. It is of interest 

 to note that the word "microscope" was coined in 1625 by Giovanni 

 Faber. Hooke is credited with the discovery of what we know 



