The Dawn of Microscopical Discovery. By C. Singer, 



:'.lT. 



reach of the unaided senses Animalcules," he reiterates, 



"(Cridones sive Dracunculi), insects, moths and little corroding 

 malignant worms and acari * swarm in the discharges and humours 

 of measles, scabies and smallpox, and both give rise to the lesions 

 and cause their ruptures." This, one of the earliest adumbrations 

 of the germ theory of disease, thus carries the analogy of scabies 

 to the somewhat similar rashes of other infectious diseases. The 

 same idea was taken up by Hauptmann's contemporary, Athanasius 

 Kircher, and was pushed to the most absurd lengths in the 

 following century by Linnaeus and his pupils.f 



The theory of the relationship of Acari to scabies was received 



TAB.XV1I d4:i6».m i} fjiM 



•<■ 1 



Fig. 38. — Sarcoptes scabiei, as figured by Ettmuller in the " Acta 

 Eruditorum " of 1682. The three figures on the right marked 

 E are Ettmuller 'a own ; the others are copied by him from 

 Heintke's work of 1G75. The dots at A are supposed to re- 

 present the natural size of the creatures. 



by most of Hauptmann's contemporaries with scepticism, but in 

 1675 one Heintke,J produced fearsome figures of hairy creatures 

 that he declared to be magnified images of mites extracted from the 

 vesicles of the disease. These monsters were probably at least in 

 part the contents of the sebaceous glands, or black heads, with 



* Among these early microscopic writers Cridones, Syronos. Dracunculi, 

 Vermiculi, Bestiola?, Animalcula, Acari are often mere synonyms. 



t Linnaeus : see "Fauna Suecica," 174G ; also Michael Baeckner in Thesis 

 " Insectorum," Holm, 1752, and Johannes Nyander in Thesis ''Exanthemata 

 Viva." Upsala, 1757. 



t " Valetudinarium infantile pro publico, perlustratione, consensu gratiosae 

 facultatis mediae apertum a praeside Michaele Ettmullcro . . . llespondente 

 Georgio Heintke," Leipsig, 1875. 



