No. 387.] THE: PRESENT STATUS OF ANATOMY. 193 
posed of numerous organs was clearly understood, but Bichat 
pointed out that the structure and function of an organ is 
dependent upon components, the tissues, which enter into its 
formation. To quote his own words: “Every animal is an 
assemblage of different organs, which, each performing a single 
function, subserve, each in its own way, the preservation of all. 
They are so many special structures in the gtneral structure 
which constitutes the individual. Now these special structures 
are themselves formed of several tissues of very different na- 
tures, and which, indeed, form the elements of these organs. 
Chemistry has its simple bodies, which form, by the various 
combinations of which they are capable, compound bodies; such 
simple bodies are heat, light, hydrogen, oxygen, carbon, nitro- 
gen, phosphorus, etc. Similarly, anatomy has its simple tissues, 
which, by their combinations in fours, sixes, eights, etc., form 
the organs.” Elements of lower grade than the organs had 
been postulated in earlier times; thus Boerhaave speaks of 
elementary fibres which form certain structures and Ascle- 
piades, still earlier, applied to anatomy the Epicurean doctrine 
of atoms. But one of these was a philosophical abstraction and 
not a scientific hypothesis, and the other a crude generalization 
not applicable to all parts of the body. Bichat’s tissue element 
is, however, accepted to-day as an individual of simpler grade 
than the organ individual, and though we do not recognize as 
perfect his definition of tissues or his enumeration of them, yet 
the ground idea is the same, except in so far as it is influenced 
by the cell theory of a later date. 
If, now, the epoch-making discoveries in the history of 
anatomy in the sixteenth, seventeenth, and eighteenth centuries 
were to be summed up briefly, there would be placed first and 
foremost the overthrow of the Galenian traditions, and the 
revival of observation by Vesalius (1516-34); next the dis- 
covery of the circulation of the blood by Harvey (1619); next 
Haller’s discovery of the irritability and contractility of nerve 
and muscle (1746), and, finally, the formulation by Bichat of his 
tissue elements and the overthrow of both the ultra-physical 
and the ultra-animistic theories of disease (1801). 
During all the period hitherto considered anatomy remained 
