H. Charlton Bastian.

The beginnings of life: being some account of the nature, modes of origin and transformations of lower organisms online

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Graham showed, that one and the same saline sub-
stance may exist with its molecules now in the crystal-
loid and now in the colloidal mode of aggregation —
according to the different influences to which it has
been subjected or under which it has been produced.
This, for instance, is the case with silica, with the
sesquioxides of chromium and iron, and with other
mineral substances. Nay, more, the absencie of any
natural barrier between the crystalloid and the colloidal
mode of aggregation may be still further seen by the



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THE BEGINNINGS OP LIFE, 39

feet that even the most typical colloids are capable of
undergoing that kind of isomeric molecular change
which converts them into crystalloids. As one of the
best instances of this we may mention the fact of the
change which blood pigment undergoes. Hsematoidin
is frequently met with in the form of oblique rhombic
crystals, and in addition there are other crystalline
forms of albumenoid substances obtainable from blood ^.
Amongst these may be included certain tetrahedral
crystals discovered by Reichert in connection with the
placenta of the guinea-pig, the behaviour of which to
reagents renders it certain that they were of an albu-
menoid or protein nature. Chlorophyll also has been
observed in a crystalline state by M. Tr^cul^, whilst
Dr. Montgomery » has depicted the results of a similar
change which a tube of myeline had undergone.
These fects suflBciently prove that no impassable bar-
rier exists between the crystalloid and the colloid
states of matter *. Do we not see that simple saline

* See an article on • Albuminous Crystallisation * in * Brit, and For.
Med. Cliir. Rev./ Oct. 1853.

' * Comptes Rendus/ t. Ixi. p. 436.

* * On the Formation of so-called Cells in Animal Bodies,' 1867.

* In a paper recently read before the Royal Society (Proceedings,
▼ol. xix. [1871] p. 455), by Dr. Marcet, entitled, * An Experimental
Inquiry into the Constitution of the Blood and the Nutrition of
Muscular Tissue,' he states, * that a mixture of colloid phosphoric
anhydride and potash can be prepared artificially by the dialysis of a
solution of chloride of potassium and phosphate of sodium, and that
the colloid mass thus obtained appears to retain the characters of the
neutral tribasic phosphate.' Dr. Marcet finds, moreover, ' that blood
contains phosphoric anhydride and iron in a perfect colloid state, or



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4b THE BEGINNINGS OE LIFE,

substances majr pass into the colloidal condition^ knd
that even typical colloids may assume a crystalloid
mode of aggregation? It surely is not difficult to
imagine, therefore, that molecular rearrangements may
take place amcmgst the constituents of ammoniacal
salts of greater complexity, whereby a more complex
colloid may be produced^-one which may diflFer in no
essential respect from th^ simplest forms of protein*
And if such a change does take place, it would be
only rational for us to suppose that the new-formed
protein would be just as prone to undergo change as
this substance generally is. If ordinary protein com-
pounds, therefore, which have been built Up in living
things, are capable of going through certain life-giving
changes, it would be quite natural to suppose that the
differently evolved protein — that which comes into
existence ^ spontaneously,* or Without the influence
of pre existing living matter — would go through similar
changes.

Wherever life-giving combinations occur, therefore,
we are entitled to look upon them as actions reiUltiilg
from the influence of physical foi-ces upon material
collocations whose molecular constitution is of such a
nature 2^ to render them most prone to undergo
rearrangements. A series of reactions takes pkce

quite undifiiiable when submitted to dialysis.' In summing up the
results of his researches, he comes to the eondusion — * That there is a
oonsfant change, as rotation in natuit, from oTstalloids to coUoids, and
from colloids to crysteUoids/



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THE BEGINNINGS OF LIFE, 41

between such material collocations and their environ-
ment, leading to further combinations, and as a result
living matter appears. Such a tendency to undergo
diange is inherent in colloidal compounds. As Prof.
Graham told us: — 'Their existence is a continual
metastasis. . . . The colloidal is, in fact, a dynamical
state of matter, the crystalloid being the statical con-
dition.'



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CHAPTER XIII.



CRYSTALS AND ORGANISMS : CAUSES WHICH DETERMINE THEIR
FORM AND STRUCTURE.

Fluidity and Solution. Molecular qualities retained. Action of Heat.
Solution a State of Chemical Combination. Modes of precipitation
of Saline Substances. Properties of all Bodies dependent upon
Molecular Composition. Allotropism. Simple and compound
Substances. Relations of Crystalloids to Colloids. Conditions
favourable to Crystallization. Slowness of Union. Influence of
weak Galvanic Currents. Dimorphism under di£ferent * Conditions.'
Changes in Colour as well as of Shape. Dr. Bennett's Cellular
Crystals. Mr. Rainey's Calculi. Fusion of these. Structure of
Starch-grains similar. Their Fusion. Albumenoid Concretions.
Mere amorphous Granules. Specks of * living * Matter. These
assume Organic Forms. Products differ as Heat acts rapidly or
slowly. Different origin of Crystals and Organisms. Views of
Maupertuis, Burdach, Schwann, Herbert Spencer, and G. H. Lewes.
Passage of not-living into ' living ' Matter, in Growth of Plants.
Influence of pre-existing Protoplasm determines the Quality of the
new Matter. Same with pre-existing Crystalline Matter. Crystalline
Polarities shown by Repair. Modifications producible by diff"erent
'Conditions.' Dimorphism of Mercuric Iodide and other Salts.
Such Modifiability should be more marked in the case of * living '
Matter.

THE States of fluidity and solution are conditions
to which most forms of matter may be reduced,
and from which all solid forms must, in accordance with
the Evolution hypothesis, have originally emerged.
Fluidity or fusion is due, for the most part, to the



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THE BEGINNINGS OF LIFE, 43

dissociating agency of heat, which tends to increase
the distance between the ultimate atoms and molecules
of bodies ^ The chemical affinities holding together
the constituent atoms or molecules of certain com-
pounds are, however, too feeble to withstand* the
dissociating influence of an intense amount of heat.
As the temperature rises, the chemical affinities which
bind tc^ether the dissimilar atoms into compound
molecules become more and more weakened, and may
be at last overcome before liquefection takes place.
Still larger is the number of compounds which are
unable to endure the disruptive agency of the higher
temperatures necessary to reduce them to the state of
gas or vapour. In the case of those substances, more-
over, which are capable of being reduced to either
physical condition by the aid of heat, innumerable

1 * Bonsen and Hopkins have shown that substances which expand
when fused have their point of fusion raised by mechanical pressure,
that is to say, since mechanical force must be overcome in melt-
ing, the tendency to melt must be overcome by heat before that
opposition can be overcome ; and the pressure required to keep them
solid at any temperature above their natural point of fusion may be
lodced upon as the mechanical representative of the force with which
they tend to fuse at that temperature. Prof. W. Thomson has shown
diat, on the contrary, water, which expands in freezing, has its point
of fiision lowered by pressure ; that is to say, since mechanical force
must be overcome by crystallizing, crystallizat'on wl not take place
under increased pressure, unless the force of crystalline polarity be
izicreased by reducing the temperature. . . . Similar principles hold true
with respect to the solubility of salts in water.* — Bakerian Lecture, * On
the Direct Correlation of Mechanical and Chemical Forces,' by H.
C. Sorby (• Proceed, of Royal Soc.* vol. xii. 1863, p. 540).



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THE BEGINNINGS OF LIFE.



diflFerences exist as to the amount of htat which is
necessary for converting thehi into the one or the other
state. In short, the particular temperatures at which
different elementary ot compound Substances afe capa-
ble of existing respectively as solids, fluids, or vapours,
varies ad infimtrnn^ in accordance with differences in
the molecular nature and propetties of the bodies
themselves. Most of theit- distinctive chettiical diarac-
ters remain, however, essentially the same^ in whatever
physical condition the matter may at the time exist—
wheth.r that of gas, fluid, or solid ^

When reduced to the state of solution^ also, bodies
lose the obvious physical characters which originally
distinguished them. Theil- individual and separate
existence has gone — their constituent molecules have
parted company, and are, for the time, more intimately
related to the molecules of the solvent. The solvent
itself may vary much in nature, though that with

' The mblectilAr reladonships of liquids and thdr tapotirs lias htta
ftirther elucidated in a recent itiefaidir by Viol Tyndall, * On tlie Action
of Rays of high RefrangibiHty npon Gaseous Matter/ ih which he inakts
the following highly interesting statements : — * i. The vaporous nitrite
of atnyl absorbs with such avidity the rays competent to decompose it that
a very small depth of the vapour quenches the efficient rays of a power-
ful beam of Solar or electric light, i. The vaporous iodide of allyl, on
the contrary, permits a beam to traverse it for long distances whhout tery
powa-iully diminishing the dietnical power of the beam. 3. The liquid
nitrite of amyl, in a stratum one quarter of an inch thick, qdenches all the
rays which could act chemically upon its vapoui*. 4. The liquid iodide
df illyl, on the contrary, in a stratum of fotir times the thickness just
mentioned, does not materially diminish the power of the beam to act
upon its vapour/ (* PhiL Trani.* 1870, p. J44.)



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THE BEGINNINQS OF LIFE, 45

whose actjpa we are most familiar is water. This
%s^A dissolve a great variety of diflperent substances.
And although the materials so dissolved lose the
characteristics which distinguished them as solid d%-
grpgaites — such as form, hardness, specific gravity, and
other physical qualities — the actual matter is still there,
in a stat^ of mole<ailar diffusion and with all its
chemical {H-op^rties comparatively unaltered. It is
recoyerat>l^ also, in the form of a solid aggregate —
either by the dissipation of the water by means of
heat, or else by the use of reagents for which the
molecules of water hc^ve a stronger affinity.

Many elementary substances and compounds that
qiimot be m^de by the agency of heat to assume the
fluid form (as well as many which can be so reduced)
are dissolved by immersion in water. And just as in-
numerable variations are met with in the behaviour
of different simple and compound substances under the
influence of a given degree of heat, so innumerable
variations exist in the behaviour of different substances
when twrought into contact with water of a given tem-
perature. Some are very soluble, some less soluble, and
others quite insoluble j these differences being depen-
dent i^pon th^ diffident properties of the molecules of
the substances in relation to those of water. A union,
which can only be termed chemical, takes place between
the molecules of the substance dissolved and that of its
solvent*; though where these molecules are complex,

^ Spealpi^ of the foroe wliiob detennines solutioii, Mr. Sorby says,



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46 THE BEGINNINGS OF LIFE.

as with salts, they may be broken up into simpler units,
which enter separately into combination with the
molecules of water. The state of solution is, therefore,
to be regarded as a new chemical combination — one
which carries with it, like many other such combi-
nations, marked diflFerences in physical quality.

In such respects, therefore, the state of solution diflFers
notably from the mere state of fluidity to which the
molecules of a simple body may be reduced by the
agency of heat.

But solution is a state of combination whose dura-
bility, like that of all other chemical combinations, is
absolutely dependent upon the strength of the affinity
existing between the molecules of the solvent and those
of the substance dissolved. Solubility, accordingly, is
amenable to the influence of all those causes which
generally tend to aflFect the stability of compounds.
A little diminution or a little increase of heat may
render a pre-existing union no longer possible. Thus,
when a hot saturated solution of alum or nitre is
allowed to cool, some of the salts crystallize out of the

(loc. cit. pp. 546, 542) :— • We cannot, I think, deny that the force
represents some modification of chemical affinity, or is, at all events,
most closely allied to it. . . . The solubility of salt in water appears to
me to result from a kind of affinity which decreases in force as the
amount of salt in solution increases. This affinity is opposed by the
crystallme polarity of the salt; and when the two forces are equal, the
solution is exactly saturated. As is well known, a change m temperature
alters this equilibrium ,* and, according to my experiments, medianical
pressure relatively increases one or other of these opposing forces,
according to the mechanical relations of the salt in dissolving.'



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THE BEGINNINGS OF LIFE. 47

solution; when heat is applied to a solution of lime,
some of it becomes precipitated ; whilst, when either
heat or cold is applied to a solution of sodic sulphate
abready at a temperature of 33'' C, some of this salt
separates from the state of solution 1. Here, as in
other cases of decomposition, the molecules of the dis-
solved substance and of the solvent, being themselves
diflferent, are diflFerently aflFected by the influence of the
same change or disturbing influence 2. And we must
suppose the amount of diflference induced to be so great
as to weaken or wholly destroy the affinity which had
previously held them together, so that the molecules of
the water under the new conditions are no longer able
to hold asunder the molecules of the substance with
which they were previously in combination. Or a
similar effect may be brought about by the addition of
a considerable quantity of a substance more soluble
than that which is already in solution 3. Thus, sodic
chloride crystallizes from its aqueous solution on the

^ Mr. Sullivan considers (* Rep. of Brit. Assoc.' 1859, p. 292) that the
solubility of very many salts (^like that of sodic sulphate) attains a maxi-
mum at some particular temperature, above or below which it diminishes.
This temperature may frequently be above 100° C; hence the common
belief that solubility always increases with rise of temperature, because
temperatures higher than 100° C are rarely resorted to. Calcic sulphate
(gypsum) b less soluble in boiling than in cold water, and is quite
insoluble in water at 140° C.

• See voL I. pp. 9&-104.

* Even saturated solutions of certain substances, however, will permit
a solution of some other salts without occasioning a precipitation of those
originally dissolved.



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48 THE BEGJNNim^ OJ* LIFE.



Edition of calcic chloride, whilst nitre does the s^me
on the addition of alcohol. Greater solubility implies
greater chemical aiBnity, under the influence of which,
the molecules of water, leaving those of the ^bstance
first dissolved, may combine with th^ new molecules,
whilst the old are free to a^regat^ in the form of a pre-
cipitated salt^ The case is only a little more complex
where what is called 'double decomposition* takes pl^ce.
But facts of a slightly different nature must ^so b^
borne in mind. Some salts which are capable of re-
maining in solution together at certain temperatures,
may be incapable of doing so when the solution i^
not maintained at a temperature within this range, In
such a case, one of two things may happen : either one
of the two salts originally dissolved may be precipitated,
or else a 'double decomposition* may take place— rleacj-
ing to the deposition of one of the alternate s^t%

' In the highly interesting memoir alroady r^rred to, Pro£. Tyndall
SAys :^-* Carbonic acid is decomposed by the solar beams in the leaves
of plants ; but here it is in presence of a substance chlorophyll, ready,
as it were, to take advantage of the loosening of the atoms by the
solar rays. The present investigation has furnished numerous cases of a
similar mode of action. All the vapours examined may be more or kss
powerfully affected in their actinic relations by the presence of a second
body with which they can interact. The presence, for example, of
nitric acid, or of hydrodiloric acid, may either greatly intensify or greatiy
diminish the visible action of the light on many vapours decomposaUe
alone or when mixed with air ; while the presence of the one or th«
other of the same acids may provoke energetic action in substances which
are wholly inactive when left to themselves.* Nitrite of amyl, nitrite of
butyl, and lienol afford good examples of this mode of action, which is
very similar to that referred to in the text, and which is often instru-
mental in aiding fermentative changes.



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THE BEGINNINGS OF LIFE. 49

whikt the other acid and base still continue in a state
of solution. This is an occurrence of much importance,
since it tends to show that chemical aflSnities which
may be held in abeyance at certain temperatures may,
at other temperatures, assert themselves, and thus lead
to the initiation of molecular combinations which
result in the emergence from the solution of a new kind
of solid aggregate.

We have illustrated our remarks hitherto by a
reference to the behaviour of simple saline substances,
though all the observations that have been made are
equally applicable to chemical substances in general.
It is quite immaterial whether we have to do with
simple substances or with highly complex bodies: the
properties of all alike are dependent upon their mole-
cular composition and nature. Molecular comfositian is
an important item even with reference to substances
which are looked upon as elementary — different modes
of composition or arrangement of the atoms sufficing to
produce what are called ^allotropic* states. We are
most familiar with these as they are presented to us in
the various forms of carbon. The differences between
the diamond, graphite, anthracite, and pure charcoal
are most striking, and yet these are all different states
of one and the same substance whose ultimate atoms
are differently grouped. Oxygen 1, sulphur 2, and

' OrdinaTy oxygen, and ozone whose molecule is supposed to be
repcesented by O4.
* Sulphur crystallizes in rhombic octahedrons belonging to the
VOL. II. E



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50 THE BEGINNINGS OF LIFE,

phosphorus*, as well as arsenic, antimony and other
metals, also exist in allotropic states in which they
exhibit wholly diflFerent properties. It will be easily
understood, therefore, that in compound substances a
greater and greater possibility of molecular rearrange-
ment arises in proportion to their atomic complexity.
Gradually, in fact, this becomes the all -important
character of a compound, and one to which the nature
of the constituent atoms is altogether subordinate. In
proof of this, one has only to refer to the multitudes
of isomers with wholly diflFerent properties which are
compounded of carbon, hydrogen, and oxygen, in the
same relative proportions.

Although so much depends, therefore, upon the
number and arrangement of the atoms in the molecule,
still the properties of the molecule can be nothing
more than the resultant of the properties of the dif-
ferent atoms— -modified by their mutual influence upon

trimetric system, and also in rhombic prisms belonging to the mono-
clinic system. The latter have a deep yellow colour and are translucent :
they always exhibit a great tendency to pass by molecular rearrange-
ment — accompanied by an evolution of heat — into the opaque, straw-
yellow, octahedral crystals.

* The two varieties of this substance are known by the name of
Normal and Red Phosphorus. The first variety is much more poisonous
than the second; it is also colourless, crystallizable in rhomboid do-
decahedra, soluble in sulphide of carbon, easily oxidizable, phospho-
rescent, and inflanmiable at a low temperature. The second form is
scarlet red, amorphous, much less soluble, non-phosphorescent, and only
inflammable at high temperatures. Mr. Lemoine has shown that heat is
the most available means for converting the one form into the other,
and that the transformation is always only partial.



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THE BEGINNINGS OF LIFE, 51

one another in that particular mode of collocation which
belongs to, and constitutes, the molecule in question.
The phenomena of allotropism, as we have previously
hinted, and various other considerations, tend to show
that even simple bodies — such as phosphorus, sulphur,
and the metallic elements — are made up of molecules
composed of similar atoms existing in a definite number
and grouping in each allotropic state or separate sub-
stance. An alteration of the number or grouping of
the atoms in the molecules, or of both, seems to be the
only way of accounting for the wholly diflFerent proper-
ties and crystalline form of one and the same sub-
stance, such as sulphur, under the influence of diflFerent
physical conditions. And thus vanishes the difference
between simple or elementary, and compound bodies.
They are all made up of molecules^ only those of
the simple substances are aggregates of similar atoms,
whilst those of compound substances are a^regates of
dissimilar atoms.

Different compound substances vary immensely in
their degree of complexity. Some, such as ordinary
acids or bases, are aggregates of simply complex mole-
culesj others are aggregates of doubly complex mole-
cules — that is to say, two simply complex molecules
combine to form a doubly complex molecule, and,
when aggregated together, these include, amongst other *
compounds, a very common class known as salts ^

* As a general rule, it may be said that decomposition follows the
reverse order. The larger molecules separate most easily; and the

E %



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52 THE BEGINNINGS OF LIFE,

Seeing that in bodies of this class a compound radicle,
such as cyanc^en (CN) or ammonium (NHJ, may
replace one of the simple metallic elements, and that
two such salts may combine together to constitute a
double salt J or that the metallic element may be re-
placed by a more complex radicle, such as urea
(C2N2H4 02) or kreatinine (C8H7N3O2), or even by
one of the still more complex bodies known as alka-
loids 1, we may be somewhat amazed at the marvellous
atomic complexity which is to be attained even by
crystallizable bodies known as salts.

In each case we have to do with atomic and mole-
cular properties, and looked at in this light, the diflFer-
ences between what are called simple and complex
substances gradually vanish. All alike have a mole-
cular constitution, though the molecules may be simple
or compound, and made up of like or unlike units.

What has been said concerning crystallizable bodies
obtains also with regard to the compounds known as
.colloids. We will not recapitulate what has been al-
ready said 2 concerning these remarkable compounds 5
we will merely state that they are supposed to be
generally characterized by the large size and complexity

constituent atoms of the simple molecules are the last to part com-
pany.

^ The composition of narcotine» for instance, is said to be Ca Hss
NO", and that of morphine, C^ H" NOe+ 2 HO. Both bodies have
distinct crystalline forms.

* See voL L pp. 88-91.



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THE BEGINNINGS OF LIFE, 53

of the molecules of which they are compounded. Prof.
Graham says : — ' It is diflScult to avoid associating the
inertness of colloids with their high equivalents^
particularly where the high number appears to be
attained by the repetition of a smaller number. The
enquiry suggests itself whether the colloid molecule
may not be constituted by the grouping together of a



Online LibraryH. Charlton BastianThe beginnings of life: being some account of the nature, modes of origin and transformations of lower organisms → online text (page 4 of 54)