46 FROM FISH TO PHILOSOPHER 



vey utilized observations on many animals— scarcely a 

 creature native to the English countryside escaped his 

 investigation— and each contributed to the a£Brmation of 

 the thesis that broke the fourteen-century-old authority 

 of Galen and laid the foundations for modem physiology 

 and medicine. 



It was shortly after Harvey's death that Marcello Mal- 

 pighi (1666), for the first time systematically exploring 

 the fine structure of the organs of the body with a mi- 

 croscope, discovered the glomeruh of the kidney— they 

 are still referred to in many texts as 'Malpighian cor- 

 puscles'—and incorrectly described them as 'glands/ 

 failing to see the minute blood vessels or capillaries 

 which he himself had just discovered in the lungs of 

 frogs. Four years previously Lorenzo Bellini had traced 

 backward from the renal pelvis the larger collecting 

 ducts of the kidneys, to see them break up into finer and 

 finer branches as dissection proceeded into the interior 

 of the organ, and demonstrated that these were not sohd 

 fibrous strands but hollow tubes— today still referred to 

 as 'Bellini's ducts/ Malpighi surmised, but did not prove, 

 that his corpuscles were connected with Bellini's ducts 

 and that they played an important part in mine for- 

 mation. 



Here the matter rested for almost two centuries, until 

 in 1842 William Bowman, using microscope equipment 

 not available in Malpighi's time, demonstrated the true 

 relations of the capillary tuft to the tubule: that in each 

 'Malpighian corpuscle' the crescent-shaped space around 

 the capillary tuft drains freely into the lumen of the 

 tubule. This space with its investing membranes is today 

 called 'Bowman's capsule.' Bowman, like Harvey and 

 Malpighi, studied every type of animal available to him: 

 his classic paper describes the 'corpuscles' and 'tubes' as 

 they appear in the badger, dog, lion, cat, mouse, squir- 

 rel, guinea pig, horse, parrot, tortoise, boa, frog, and 

 common eel, as well as in man. 



It remained for the physiologist Carl Ludwig, in 1842, 



