THE GENERAL CONSTITUTION OF LIVING BEINGS. §3 
the sum of the properties inherent in each sort of element, 
while the characteristics of the fundamental element pre- 
dominate. The accessory elements in a manner restrain 
the too great activity of this latter, and thus take part in 
giving to the tissue properties of a secondary order indeed, 
but indispensable to the discharge of its duty, which is thus 
the result of manifold properties. When the texture of 
these organic webs is studied under a microscope, we are 
often astonished at the prodigious complexity they exhibit. 
Nothing is so curious as the disposition and arrangement 
of all these tiny centres of life, some round, others polyhe- 
dric, others thread-like, others again tubular, and all so 
small that the humblest flesh-worm is a monster beside 
them. Sometimes the fibres are tangled inextricably, like 
dense ivy around an aged trunk; sometimes there is a 
singular net, formed by the capillaries with fine meshes, 
in which the cells crowd and crush themselves out of shape. 
Sometimes we find clusters in which little bladders are 
arranged along a crooked channel; sometimes there are 
layers, piled one on another, resembling geological strata. 
In a word, the arrangement of the elements is exceedingly 
diversified, and, if we might say that the tissues are words 
in which anatomical elements stand for the letters, it must 
be added that the order of the latter is much more compli- 
cated than is the case with the terms of spoken language, 
and very differently too. 
The nerve-tissue, the real masterpiece of vital force, has 
been well understood only since histology has disclosed to 
us all the elements of that fragile whitish pulp. The 
structure of the ganglia, the connections they have with 
the nerves, the difference between nerve-tubes and nerve- 
cells, have been made out by Robin. He it was, too, who 
discovered the lymphatic vessels of the brain-substance. 
These lymphatics encircle the blood-vessels traversing the 
central nerve-tissues in such a way that the latter are com- 
