ANIMAL TISSUES. 9 
The Tissues of Animals. 
Nature, in the structure of animals, has exhibited inconceivable 
resources of art. Not only is the body as a whole, not only are its 
grosser parts, but even the smallest parts of the organs are ma- 
chinery; and the knife of the anatomist exhibits to us, even to the 
simplest fibre, nothing but parts constructed for a purpose. The 
whole body consists of many members: the members themselves 
consist of muscles, vessels, and nerves; the muscles again of 
tissues, vessels, fibres, &c. Such a body may well be called 
organised. . 
Tn order to form an idea of the texture of animals, we must go 
to work as the chemist does. He divides the parts which compose 
bodies into proximate and ultimate constituents, and terms those 
constituents ultimate, or elements (elementa), which by his art he 
can separate no further into heterogeneous parts. In the same way 
we find in the textures of animals proximate and ultimate con- 
stituents. Of the last, or the organic elements (elementa organica), 
we shall speak hereafter: the first question is—what are the proxi- 
mate constituents? (partes constituentes proxime). They are called 
Tissues (Tele). 
BicuAr was the founder of the science of the organic tissues in 
man, and named it General Anatomy. In the investigation of the 
tissues he had recourse to chemical reagents, to maceration and 
partial decomposition in water. He described each tissue according 
to its physical and chemical properties, its physiological phno- 
mena and its morbid changes. After him this science was ad- 
vanced by Mrcket, Heustncer, and Biciarp! in the same spirit. 
Within the last ten years it has received a totally different direction 
through microscopic research. By means of it General Anatomy 
has become, for the most part, Microscopic Anatomy. Our immortal 
LEEUWENHOECK, about a century and a half ago, had collected 
much material which remained almost unused; until, in our day, 
with the improvement of the compound microscope, a more general 
interest in such enquiries has been excited, and the importance of 
the knowledge of the minutest organic constituents to accurate 
1 Here it may suftice to refer to the well-written and succinct manual of the last 
named author: Elémens d’ Anatomie générale (2™ édit. Paris, 1827. Svo.) 
