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Analyses of Books. 
green matter of leaves decomposes the carbonic acid of the air, 
are of the dissymmetric order.” He is inclined to think that 
“ a s manifested to us must be a function of the dissymmetry 
of the universe or of the consequences that follow in its train.” 
He suggests the attempt of introducing a manifestation of dis- 
symmetry among the forms of crystals by means of magnets. 
“ At Lille he contrived a piece of clockwork intended to keep a 
plant in continual rotatory motion first in one direction and then 
in another.” He further proposes, “ with the view of influencing 
the vegetation of certain plants, to invert by means of a heliostat 
and a reflecting mirror the motion of the solar rays which should 
strike them from the birth of their earliest shoots.” 
He is further quoted as saying “ When the attempt is made 
to introduce into living species primordial substances, inverse to 
those now existing, the great difficulty will be to master the ten- 
dency proper to the species, a tendency which is potential in the 
germ of each of them. In this germ, it is to be feared, the dis- 
symmetry of the dissymmetric primordial substances which it 
embraces will always manifest itself. Ah ! if spontaneous gene- 
ration were possible ; if we could form from mineral matter a 
living cell, how much more accessible would the problem become ! 
However this may be, we must seek, by all possible means, to 
produce molecular dissymmetry by the application of forces 
which have a dissymmetric acftion ; we must invoke the acftion 
of solenoid or helix.” 
It is, however, only fair to notice here the criticism of Professor 
Tyndall. He reminds us, in his introductory chapter, that the 
molecular dissymmetry upon which Pasteur lays such great 
emphasis is simply a hypothesis to account for a fadt — the power 
of causing the plane of polarisation to rotate. Now previous to 
1:845 Faraday had succeeded, both by helices and magnets, in 
causing the plane of polarisation in solids and liquids, previously 
neutral, to rotate. If such rotatory power is a proof of molecular 
dissymmetry, Faraday succeeded in conferring this power upon 
more than 150 substances. But that they were thus brought any 
the nearer to vitality it nowise appears. 
But we must now pass to an apparently very remote subjecft, 
the “vaccines,” — as they have been unhappily named — which 
Pasteur has devised for certain zymotic diseases. The one basis 
common to Jenner and to Pasteur is the proposition that a man 
can have ordinarily certain diseases only once in his lifetime, and 
that if he recovers he will ordinarily enjoy a complete immunity. 
Ordinarily, for there appear to be exceptional cases in which a 
single attack of yellow fever, black plague, smallpox, &c., does 
not permanently exhaust the susceptibility of the patient. But 
beyond this fundamental proposition, Jenner and Pasteur diverge 
completely from each other. Jenner observed, or thought that 
he had observed, that a disease different from smallpox, and not 
naturally occurring in man, could, if transferred to the human 
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