§ =73.= Robert Boyle (1626-1691) had def_Alchemy: Ancient and Modern Being a Brief Account of the Alchemistic Doctrines, and Their Relations, to Mysticism on the One Hand, and to Recent Discoveries in Physical Science on the Other Hand; Together with Some Particulars Regarding the Lives and Teachings of the Most Noted Alchemists

which could not be decomposed, but which could enter into combination

with other elements giving compounds capable of decomposition into these

original elements. Hence, the metals were classed among the elements,

since they had defied all attempts to decompose them. Now, it must be

noted that this definition is of a negative character, and, although it

is convenient to term “elements” all substances which have so far defied

decomposition, it is a matter of impossibility to decide what substances

are true elements with absolute certainty; and the possibility, however

faint, that gold and other metals are of a compound nature, and hence

the possibility of preparing gold from the “base” metals or other

substances, must always remain. This uncertainty regarding the elements

appears to have generally been recognised by the new school of chemists,

but this having been so, it is the more surprising that their criticism

of alchemistic art was not less severe.

The Stoichiometric Laws.

§ =74.= With the study of the relative weights in which substances

combine, certain generalisations or “natural laws” of supreme importance

were discovered. These stoichiometric laws, as they are called, are as

follows:--

1. “The Law of Constant Proportion”--_The same chemical compound always

contains the same elements, and there is a constant ratio between the

weights of the constituent elements present._

2. “The Law of Multiple Proportions”--_If two substances combine

chemically in more than one proportion, the weights of the one which

combine with a given weight of the other, stand in a simple rational

ratio to one another._

3. “The Law of Combining Weights”--_Substances combine either in the

ratio of their combining numbers, or in simple rational multiples or

submultiples of these numbers._ (The weights of different substances

which combine with a given weight of some particular substance, which is

taken as the unit, are called the combining numbers of such substances

with reference to this unit. The usual unit now chosen is 8 grammes of

Oxygen.)[90]

[90] In order that these laws may hold good, it is, of course,

necessary that the substances are weighed under precisely similar

conditions. To state these laws in a more absolute form, we can

replace the term “weight” by “mass,” or in preference, “inertia”;

for the inertias of bodies are proportional to their weights,

providing that they are weighed under precisely similar conditions.

For a discussion of the exact significance of these terms “mass” and

“inertia,” the reader is referred to the present writer’s _Matter,

Spirit and the Cosmos_ (Rider, 1910), Chapter I., “On the Doctrine

of the Indestructibility of Matter.”

As examples of these laws we may take the few following simple facts:--

1. Pure water is found always to consist of oxygen and hydrogen combined

in the ratio of 1·008 parts by weight of the latter to 8 parts by weight

of the former; and pure sulphur-dioxide, to take another example, is

found always to consist of sulphur and oxygen combined in the ratio of

8·02 parts by weight of sulphur to 8 parts by weight of oxygen. (The Law

of Constant Proportion.)

2. Another compound is known consisting only of oxygen and hydrogen,

which, however, differs entirely in its properties from water. It is

found always to consist of oxygen and hydrogen combined in the ratio of

1·008 parts by weight of the latter to 16 parts by weight of the former,

_i.e._, in it a definite weight of hydrogen is combined with an amount

of oxygen _exactly twice_ that which is combined with the same weight of

hydrogen in water. No definite compound has been discovered with a

constitution intermediate between these two. Other compounds consisting

only of sulphur and oxygen are also known. One of these (viz.,

sulphur-trioxide, or sulphuric anhydride) is found always to consist of

sulphur and oxygen combined in the ratio of 5·35 parts by weight of

sulphur to 8 parts by weight of oxygen. We see, therefore, that the

weights of sulphur combined with a definite weight of oxygen in the two

compounds called respectively “sulphur-dioxide” and “sulphur-trioxide,”

are in the proportion of 8·02 to 5·35, _i.e._, 3 : 2. Similar simple

ratios are obtained in the case of all the other compounds. (The Law of

Multiple Proportions.)

3. From the data given in (1) above we can fix the combining number of

hydrogen as 1·008, that of sulphur as 8·02. Now, compounds are known

containing sulphur and hydrogen, and, in each case, the weight of

sulphur combined with 1·008 grammes of hydrogen is found always to be

either 8·02 grammes or some multiple or submultiple of this quantity.

Thus, in the simplest compound of this sort, containing only hydrogen

and sulphur (viz., sulphuretted-hydrogen or hydrogen sulphide), 1·008

grammes of hydrogen is found always to be combined with 16·04 grammes of

sulphur, _i.e._, exactly twice the above quantity. (The Law of Combining

Weights.)

Berthollet (1748-1822) denied the truth of the law of constant

proportion, and a controversy ensued between this chemist and Proust

(1755-1826), who undertook a research to settle the question, the

results of which were in entire agreement with the law, and were

regarded as completely substantiating it.

[Illustration: PLATE 16.

[by Worthington, after Allen]

PORTRAIT OF JOHN DALTON.

_To face page 100_]]

Dalton’s Atomic Theory.

§ =75.= At the beginning of the nineteenth century, John Dalton (see

plate 15) put forward his Atomic Theory in explanation of these facts.

This theory assumes (1) that all matter is made up of small indivisible

and indestructible particles, called “atoms”; (2) that all atoms are

_not_ alike, there being as many different sorts of atoms as there are

elements; (3) that the atoms constituting any one element are exactly

alike and are of definite weight; and (4) that compounds are produced by

the combination of different atoms. Now, it is at once evident that if

matter be so constituted, the stoichiometric laws must necessarily

follow. For the smallest particle of any definite compound (now called a

“molecule”) must consist of a definite assemblage of different atoms,

and these atoms are of definite weight: whence the law of constant

proportion. One atom of one substance may combine with 1, 2, 3 . . .

atoms of some other substance, but it cannot combine with some

fractional part of an atom, since the atoms are indivisible: whence the

law of multiple proportions. And these laws holding good, and the atoms

being of definite weight, the law of combining weights necessarily

follows. Dalton’s Atomic Theory gave a simple and intelligible

explanation of these remarkable facts regarding the weights of

substances entering into chemical combination, and, therefore, gained

universal acceptance. But throughout the history of Chemistry can be

discerned a spirit of revolt against it as an explanation of the

absolute constitution of matter. The tendency of scientific philosophy

has always been towards Monism as opposed to Dualism, and here were not

merely two eternals, but several dozen; Dalton’s theory denied the unity

of the Cosmos, it lacked the unifying principle of the alchemists. It is

only in recent times that it has been recognised that a scientific

hypothesis may be very useful without being altogether true. As to the

usefulness of Dalton’s theory there can be no question; it has

accomplished that which no other hypothesis could have done; it rendered

the concepts of a chemical element, a chemical compound and a chemical

reaction definite; and has, in a sense, led to the majority of the

discoveries in the domain of Chemistry that have been made since its

enunciation. But as an expression of absolute truth, Dalton’s theory, as

is very generally recognised nowadays, fails to be satisfactory. In the

past, however, it has been the philosophers of the materialistic school

of thought, rather than the chemists _quâ_ chemists, who have

insisted on the absolute truth of the Atomic Theory; Kekulé, who by

developing Franklin’s theory of atomicity or valency[91] made still more

definite the atomic view of matter, himself expressed grave doubts as to

the absolute truth of Dalton’s theory; but he regarded it as

_chemically_ true, and thus voices what appears to be the opinion of the

majority of chemists nowadays, namely, there are such things as chemical

atoms and chemical elements, incapable of being decomposed by purely

chemical means, but that such are not absolute atoms or absolute

elements, and consequently not impervious to all forms of action. But

of this more will be said later.

[91] The term “valency” is not altogether an easy one to define; we

will, however, here do our best to make plain its significance. In a

definite chemical compound we must assume that the atoms

constituting each molecule are in some way bound together (though

not, of course, rigidly), and we may speak of “bonds” or “links of

affinity,” taking care, however, not to interpret such terms too

literally. Now, the number of “affinity links” which one atom can

exert is not unlimited; indeed, according to the valency theory as

first formulated, it is fixed and constant. It is this number which

is called the “valency” of the element; but it is now known that the

“valency” in most cases can vary between certain limits. Hydrogen,

however, appears to be invariably univalent, and is therefore taken

as the unit of valency. Thus, Carbon is quadrivalent in the

methane-molecule, which consists of one atom of carbon combined

with four atoms of hydrogen; and Oxygen is divalent in the

water-molecule, which consists of one atom of oxygen combined with

two atoms of hydrogen. Hence, we should expect to find one atom of

carbon combining with two of oxygen, which is the case in the

carbon-dioxide--(carbonic anhydride)--molecule. For a development of

the thesis, so far as the compounds of carbon are concerned, that

each specific “affinity link” corresponds in general to a definite

and constant amount of energy, which is evolved as heat on

disruption of the bond, the reader is referred to the present

writer’s monograph _On the Calculation of Thermo-Chemical Constants_

(Arnold, 1909). The phenomena of valency find their explanation in

modern views concerning the constitution of atoms (see § 81).

The Determination of the Atomic Weights of the Elements.

§ =76.= With the acceptance of Dalton’s Atomic Theory, it became

necessary to determine the atomic weights of the various elements,

_i.e._, not the absolute atomic weights, but the relative weights of the

various atoms with reference to one of them as unit.[92] We cannot in

this place enter upon a discussion of the various difficulties, both of

an experimental and theoretical nature, which were involved in this

problem, save to remark that the correct atomic weights could be arrived

at only with the acceptance of Avogadro’s Hypothesis. This hypothesis,

which is to the effect that equal volumes of different gases measured at

the same temperature and pressure contain an equal number of gaseous

molecules, was put forward in explanation of a number of facts connected

with the physical behaviour of gases; but its importance was for some

time unrecognised, owing to the fact that the distinction between atoms

and molecules was not yet clearly drawn. A list of those chemical

substances at present recognised as “elements,” together with their

atomic weights, will be found on pp. 106, 107.

[92] Since hydrogen is the lightest of all known substances, the

unit, Hydrogen = 1, was at one time usually employed. However, it

was seen to be more convenient to express the atomic weights in

terms of the weight of the oxygen-atom, and the unit, Oxygen = 16 is

now always employed. This value for the oxygen-atom was chosen so

that the approximate atomic weights would in most cases remain

unaltered by the change.

Prout’s Hypothesis.

§ =77.= It was observed by a chemist of the name of Prout, that, the

atomic weight of hydrogen being taken as the unit, the atomic weights

of nearly all the elements approximated to whole numbers; and in 1815 he

suggested as the reason for this regularity, that all the elements

consist solely of hydrogen. Prout’s Hypothesis received on the whole a

very favourable reception; it harmonised Dalton’s Theory with the grand

concept of the unity of matter--all matter was hydrogen in essence; and

Thomas Thomson undertook a research to demonstrate its truth. On the

other hand, however, the eminent Swedish chemist, Berzelius, who had

carried out many atomic weight determinations, criticised both Prout’s

Hypothesis and Thomson’s research (which latter, it is true, was

worthless) in most severe terms; for the hypothesis amounted to

this--that the decimals in the atomic weights obtained experimentally by

Berzelius, after so much labour, were to be regarded as so many errors.

In 1844, Marignac suggested half the hydrogen atom as the unit, for the

element chlorine, with an atomic weight of 35·5, would not fit in with

Prout’s Hypothesis as originally formulated; and later, Dumas suggested

one-quarter. With this theoretical division of the hydrogen-atom, the

hypothesis lost its simplicity and charm, and was doomed to downfall.

Recent and most accurate atomic weight determinations show clearly that

the atomic weights are not exactly whole numbers, but that,

nevertheless, the majority of them (if expressed in terms of O = 16 as

the unit) do approximate very closely to such. The Hon. R. J. Strutt has

recently calculated that the probability of this occurring, in the case

of certain of the commoner elements, by mere chance is exceedingly small

(about 1 in 1,000),[93] and several attempts to explain this remarkable

fact have been put forward. Modern scientific speculations concerning

the constitution of atoms tend towards a modified form of Prout’s

hypothesis, or to the view that the atoms of other elements are, in a

manner, polymerides of hydrogen and helium atoms. As has been pointed

out, it is possible, according to modern views, for elements of

different atomic weight to have identical chemical properties, since

these latter depend only upon the number of free electrons in the atom

and not at all upon the massive central nucleus. By a method somewhat

similar to that used for determining the mass of kathode particles (see

§ 79), but applied to positively charged particles, Sir Joseph Thomson

and Dr. F. W. Aston discovered that the element neon was a mixture of

two isotopic elements in unequal proportions, one having an atomic mass

of 20, the other (present only to a slight extent) having an atomic mass

of 22. Dr. Aston has perfected this method of analysing mixtures of

isotopes and determining their atomic masses.[94] The results are of

great interest. The atomic weight of hydrogen, 1·008, is confirmed. The

elements helium, carbon, nitrogen, oxygen, fluorine, phosphorus,

sulphur, arsenic, iodine and sodium are found to be simple bodies with

whole-number atomic weights. On the other hand, boron, neon, silicon,

chlorine, bromine, krypton, xenon, mercury, lithium, potassium and

rubidium are found to be mixtures. What is specially of interest is that

the indicated atomic mass of each of the constituents is a whole number.

Thus chlorine, whose atomic weight is 35·46, is found to be a mixture of

two chemically-identical elements whose atomic weights are 35 and 37.

Some of the elements, _e.g._, xenon, are mixtures of more than two

isotopes.

[93] Hon. R. J. STRUTT: “On the Tendency of the Atomic Weights to

approximate to Whole Numbers,” _Philosophical Magazine_, [6], vol.

i. (1901), pp. 311 _et seq._

[94] F. W. ASTON: “Mass-spectra and Atomic Weights,” _Journal of the

Chemical Society_, vol. cix. (1921), pp. 677 _et seq._

It is highly probable that what is true of the elements investigated by

Dr. Aston is true of the remainder. It appears, therefore, that the

irregularities presented by the atomic weights of the ordinary elements,

which have so much puzzled men of science in the past, are due to the

fact that these elements are, in many cases, mixtures. As concerns

hydrogen, it is only reasonable to suppose that the close packing of

electrically charged particles should give rise to a slight decrease in

their total mass, so that the atomic weights of other elements referred

to H = 1 should be slightly less than whole numbers, or, what is the

same thing, that the atomic weight of hydrogen referred to O = 16 should

be slightly more than unity.

The “Periodic Law.”

§ =78.= A remarkable property of the atomic weights was discovered, in

the sixties, independently by Lothar Meyer and Mendeléeff. They found

that the elements could be arranged in rows in the order of their atomic

weights so that similar elements would be found in the same columns. A

modernised form of the Periodic Table will be found on pp. 106, 107. It

will be noticed, for example, that the “alkali” metals, Lithium, Sodium,

Rubidium and Cæsium, which resemble one another very closely, fall in

Column 1; the “alkaline earth” metals occur together in Column 2; though

in each case these are accompanied by certain elements with somewhat

different properties. Much the same holds good in the case of the other

columns of this Table; there is manifested a remarkable regularity, with

certain still more remarkable divergences (see notes appended to Table

on pp. 106, 107). This regularity exhibited by the “elements” is of

considerable importance, since it shows that, in general, the properties

of the “elements” are _periodic_ functions of their atomic weights; and,

together with certain other remarkable properties of the “elements,”

distinguishes them sharply from the “compounds.” It may be concluded

with tolerable certainty, therefore, that if the “elements” are in

reality of a compound nature, they are all, in general, compounds of a

like nature distinct from that of other compounds.

THE PERIODIC TABLE OF THE CHEMICAL ELEMENTS.

+-------+-------+-------+-------+-------+-------+-------+-------+--------+

| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |

+-------+-------+-------+-------+-------+-------+-------+-------+--------+

| |gen][a]| | | | | |gen | |

| |[H = | | | | | |H = | |

| |1·008] | | | | | |1·008 | |

+-------+-------+-------+-------+-------+-------+-------+-------+--------+

| | |num | | |gen | |rine | |

|He = |Li = |Gl = |B = |C = |N = |O = |F = | |

|4·00 |6·94 |9·1 |10·9 |12·005 |14·008 |16·00 |19·0 | |

+-------+-------+-------+-------+-------+-------+-------+-------+--------+

|Ne = |Na = |Mg = |Al = |Si = |P = |S = |Cl = | |

|20·2 |23·00 |24·32 |27·1 |28·3 |31·04 |32·06 |35·46 | |

+-------+-------+-------+-------+-------+-------+-------+-------+--------+

| | | | | | | | |55·84[c]|

|A = |K = |Ca = |Sc = |Ti = |V = |Cr = |Mn = |Cobalt |

|39·9 |39·10 |40·07 |45·1 |48·1 |51·0 |52·0 |54·93 |Co = |

| | | | | | | | |58·97 |

| | | | | | | | |Ni = |

| | | | | | | | |58·68 |

+-------+-------+-------+-------+-------+-------+-------+-------+--------+

| |Cu = |Zn = |Ga = |Ge = |As = |Se = |Br = | |

| |63·57 |65·37 |70·1 |72·5 |74·96 |79·2 |79·92 | |

+-------+-------+-------+-------+-------+-------+-------+-------+--------+

|Kr = |Rb = |Sr = |Y = |Zr = |Cb = |Mo = | |Ru = |

|82·92 |85·45 |87·63 |89·33 |90·6 |93·1 |96·0 | |101·7 |

| | | | | | | | |Rh = |

| | | | | | | | |102·9 |

| | | | | | | | |Pd = |

| | | | | | | | |106·7 |

+-------+-------+-------+-------+-------+-------+-------+-------+--------+

| | | | | |ny |rium |[d] | |

| |Ag = |Cd = |In = |Sn = |Sb = |Te = |I (or | |

| |107·88 |112·40 |114·8 |118·7 |120·2 |127·5 |J) = | |

| | | | | | | |126·92 | |

+-------+-------+-------+-------+-------+-------+-------+-------+--------+

|Xenon |Cæsium |Barium |Lantha-|Cerium | ? | ? | ? | ? |

| | | |num |[e] | | | | |

|Xe = |Cs = |Ba = |La = |Ce = | | | | |

|130·2 |132·81 |137·37 |139·0 |140·25 | | | | |

+-------+-------+-------+-------+-------+-------+-------+-------+--------+

| | ? | ? | ? | ? | ? | ? | ? | |

+-------+-------+-------+-------+-------+-------+-------+-------+--------+

| ? | ? | ? | ? | ? |Tanta- |Tung- | ? |Osmium |

| | | | | |lum |sten | |Os = |

| | | | | |Ta = |W = | |190·9 |

| | | | | |181·5 |184·0 | |Iridium |

| | | | | | | | |Ir = |

| | | | | | | | |193·1 |

| | | | | | | | |Pt = |

| | | | | | | | |195·2 |

+-------+-------+-------+-------+-------+-------+-------+-------+--------+

| |Au = |Hg = |Tl = |Pb = |Bi = |(210) | | |

| |197·2 |200·6 |204·0 |207·20 |208·0 | | | |

+-------+-------+-------+-------+-------+-------+-------+-------+--------+

|(Niton)| |Ra = | ? |Th = | ? |U = | | |

| 222·0 | |226·0 | |232·15 | |238·2 | | |

+-------+-------+-------+-------+-------+-------+-------+-------+--------+

NOTES.

There are several somewhat different forms of this Periodic Table.

This is one of the simplest, but it lacks certain advantages of some

of the more complicated forms. The atomic weights given are those of

the International Atomic Weights Committee for 1920-1. They are

calculated on the basis, Oxygen = 16. The number of decimal places

given in each case indicates the degree of accuracy with which each

atomic weight has been determined. The letter or letters underneath

the name of each element is the symbol by which it is invariably

designated by chemists.

The number above each column indicates the valency which the

elements of each group exhibit towards oxygen. Many of the elements

are exceptional in this respect.

[a]: The exact position of Hydrogen is in dispute.

[b]: The positions of Argon and Potassium have been inverted in

order that these elements may fall in the right columns with the

elements they resemble; [d]: so also have the positions of Tellurium

and Iodine.

[c]: The whole of “Group 8” forms an exception to the Table.

[e]: There are a number of ill-defined rare earth metals with atomic

weights lying between those of Cerium and Tantalum. They all appear

to resemble the elements of “Group 3,” so that their positions in

the Table cannot be decided with accuracy.

It is now some years since the late Sir William Crookes attempted to

explain the periodicity of the properties of the elements on the theory

that they have all been evolved by a conglomerating process from some

primal stuff--the protyle--consisting of very small particles. He

represented the action of this generative cause by means of a “figure of

eight” spiral, along which the elements are placed at regular intervals,

so that similar elements come underneath one another, as in Mendeléeff’s

table, though the grouping differs in some respects. The slope of the

curve is supposed to represent the decline of some factor (_e.g._,

temperature) conditioning the process, which process is assumed to be of

a recurrent nature, like the swing of a pendulum. After the completion

of one swing (to keep to the illustration of a pendulum) whereby one

series of elements is produced, owing to the decline of the

above-mentioned factor, the same series of elements is not again the

result as would otherwise be the case, but a somewhat different series

is produced, each member of which resembles the corresponding member of

the former series. Thus, if the first series contains, for example,

helium, lithium, carbon, &c., the second series will contain instead,

argon, potassium, titanium, &c. The whole theory, though highly

interesting, is, however, by no means free from defects.

The Corpuscular Theory of Matter.

§ =79.= We must now turn our attention to those recent views of the

constitution of matter which originated to a great extent in the

investigations of the passage of electricity through gases at very low

pressures. It will be possible, however, on the present occasion, to

give only the very briefest account of the subject; but a fuller

treatment is rendered unnecessary by the fact that these and allied

investigations and the theories to which they have given rise have been

fully treated in several well-known works, by various authorities on the

subject, which have appeared during the last few years.[95]

[95] We have found Prof. Harry Jones’ _The Electrical Nature of

Matter and Radioactivity_ (1906), Mr. Soddy’s _Radioactivity_

(1904), and Mr. Whetham’s _The Recent Development of Physical

Science_ (1909) particularly interesting. Mention, of course, should

also be made of the standard works of Prof. Sir J. J. Thomson and

Prof. Rutherford.

When an electrical discharge is passed through a high-vacuum tube,

invisible rays are emitted from the kathode, generally with the

production of a greenish-yellow fluorescence where they strike the

glass walls of the tube. These rays are called “kathode rays.” At one

time they were regarded as waves in the ether, but it was shown by Sir

William Crookes that they consist of small electrically charged

particles, moving with a very high velocity. Sir J. J. Thomson was able

to determine the ratio of the charge carried by these particles to their

mass or inertia; he found that this ratio was constant whatever gas was

contained in the vacuum tube, and much greater than the corresponding

ratio for the hydrogen ion (electrically charged hydrogen atom) in

electrolysis. By a skilful method, based on the fact discovered by Mr.

C. T. R. Wilson, that charged particles can serve as nuclei for the

condensation of water-vapour, he was further able to determine the value

of the electrical charge carried by these particles, which was found to

be constant also, and equal to the charge carried by univalent ions,

_e.g._, hydrogen, in electrolysis. Hence, it follows that the mass of

these kathode particles must be much smaller than the hydrogen ion, the

actual ratio being about 1 : 1700. The first theory put forward by Sir

J. J. Thomson in explanation of these facts, was that these kathode

particles (“corpuscles” as he termed them) were electrically charged

portions of matter, much smaller than the smallest atom; and since the

same sort of corpuscle is obtained whatever gas is contained in the

vacuum tube, it is reasonable to conclude that the corpuscle is the

common unit of all matter.

Proof that the Electrons are not Matter.

§ =80.= This eminent physicist, however, had shown mathematically that a

charged particle moving with a very high velocity (approaching that of

light) would exhibit an appreciable increase in mass or inertia due to

the charge, the magnitude of such inertia depending on the velocity of

the particle. This was experimentally verified by Kaufmann, who

determined the velocities, and the ratios between the electrical charge

and the inertia, of various kathode particles and similar particles

which are emitted by compounds of radium (see §§ 89 and 90). Sir J. J.

Thomson calculated these values on the assumption that the inertia of

such particles is entirely of electrical origin, and thereby obtained

values in remarkable agreement with the experimental. There is,

therefore, no reason for supposing the corpuscle to be matter at all;

indeed, if it were, the above agreement would not be obtained. As

Professor Jones says: “Since we know things only by their properties,

and since all the properties of the corpuscle are accounted for by the

electrical charge associated with it, why assume that the corpuscle

contains anything but the electrical charge? It is obvious that there is

no reason for doing so.

“_The corpuscle is, then, nothing but a disembodied electrical charge_,

containing nothing material, as we have been accustomed to use that

term. It is electricity, and nothing but electricity. With this new

conception a new term was introduced, and, now, instead of speaking of

the corpuscle we speak of the _electron_.”[96] Applying this

modification to the above view of the constitution of matter, we have

what is called “the electronic theory,” namely, that the material atoms

consist of electrons, or units of electricity in rapid motion; which

amounts to this--that matter is simply an electrical phenomenon.

[96] H. C. JONES: _The Electrical Nature of Matter and

Radioactivity_ (1906), p. 21.

The Electronic Theory of Matter.

§ =81.= Sir J. J. Thomson has elaborated this theory of the nature and

constitution of matter; he has shown what systems of electrons would be

stable, and has attempted to find therein the significance of

Mendeléeff’s generalisation and the explanation of valency. There can be

no doubt that there is a considerable element of truth in the electronic

theory of matter; the one characteristic property of matter, _i.e._,

inertia, can be accounted for electrically. The fundamental difficulty

is that the electrons are units of negative electricity, whereas matter

is electrically neutral. Several theories have been put forward to

surmount this difficulty. Certainly the electron is a constituent of

matter; but is it the sole constituent? Recent research indicates that,

as already pointed out, all atoms consist of two distinct portions, a

massive central nucleus, whose net charge is positive, surrounded by a

number of electrons, just sufficient to neutralize this charge. The

point of greatest interest is that the indicated number of free

electrons is exactly the number which expresses the position of the

element in the Periodic Table, reckoning helium as 2, lithium as 3, and

so on; and it would seem that the chemical properties of the elements

are determined entirely by these electrons, and are, therefore, not,

strictly speaking, periodic functions of their atomic weights, as was

formerly thought (§ 78), but of their atomic numbers. The exact nature

of the nuclei of the various atoms has yet to be determined: in the

case of the atoms heavier than helium they would appear to be made up of

the nuclei of hydrogen and (or) helium atoms together with--in many

cases--electrons insufficient in number to neutralize the positive

charges associated with these.

The Etheric Theory of Matter.

§ =82.= The analysis of matter has been carried a step further. A

philosophical view of the Cosmos involves the assumption of an

absolutely continuous and homogeneous medium filling all space, for an

absolute vacuum is unthinkable, and if it were supposed that the stuff

filling all space is of an atomic structure, the question arises, What

occupies the interstices between its atoms? This ubiquitous medium is

termed by the scientists of to-day “the Ether of Space.” Moreover, such

a medium as the Ether is demanded by the phenomena of light. It appears,

however, that the ether of space has another and a still more important

function than the transmission of light: the idea that matter has its

explanation therein has been developed by Sir Oliver Lodge. The evidence

certainly points to the conclusion that matter is some sort of

singularity in the ether, probably a stress centre. We have been too

much accustomed to think of the ether as something excessively light and

quite the reverse of massive or dense, in which it appears we have been

wrong. Sir Oliver Lodge calculates that the density of the ether is far

greater than that of the most dense forms of matter; not that matter is

to be thought of as a rarefaction of the ether, for the ether within

matter is as dense as that without. What we call matter, however, is not

a continuous substance; it consists, rather, of a number of widely

separated particles, whence its comparatively small density compared

with the perfectly continuous ether. Further, if there is a difficulty

in conceiving how a perfect fluid like the ether can give rise to a

solid body possessed of such properties as rigidity, impenetrability and

elasticity, we must remember that all these properties can be produced

by means of motion. A jet of water moving with a sufficient velocity

behaves like a rigid and impenetrable solid, whilst a revolving disc of

paper exhibits elasticity and can act as a circular saw.[97] It appears,

therefore, that the ancient doctrine of the alchemistic essence is

fundamentally true after all, that out of the “One Thing” all material

things have been produced by adaptation or modification; and, as we have

already noticed (§ 60), there also appears to be some resemblance

between the concept of the electron and that of the seed of gold, which

seed, it should be borne in mind, was regarded by the alchemists as the

common seed of all metals.

[97] See Sir OLIVER LODGE, F.R.S.: _The Ether of Space_ (1909).

Further Evidence of the Complexity of the Atoms.

§ =83.= There are also certain other facts which appear to demand such a

modification of Dalton’s Atomic Theory as is found in the Electronic

Theory. One of the characteristics of the chemical elements is that each

one gives a spectrum peculiar to itself. The spectrum of an element

must, therefore, be due to its atoms, which in some way are able, at a

sufficiently high temperature, to act upon the ether so as to produce

vibrations of definite and characteristic wave-length. Now, in many

cases the number of lines of definite wave-length observed in such a

spectrum is considerable, for example, hundreds of different lines have

been observed in the arc-spectrum of iron. But it is incredible that an

atom, if it were a simple unit, would give rise to such a number of

different and definite vibrations, and the only reasonable conclusion is

that the atoms must be complex in structure. We may here mention that

spectroscopic examination of various heavenly bodies leads to the

conclusion that there is some process of evolution at work building up

complex elements from simpler ones, since the hottest nebulæ appear to

consist of but a few simple elements, whilst cooler bodies exhibit a

greater complexity.

Views of Wald and Ostwald.

§ =84.= Such modifications of the atomic theory as those we have briefly

discussed above, although profoundly modifying, and, indeed,

controverting the philosophical significance of Dalton’s theory as

originally formulated, leave its chemical significance practically

unchanged. The atoms can be regarded no longer as the eternal,

indissoluble gods of Nature that they were once supposed to be; thus,

Materialism is deprived of what was thought to be its scientific

basis.[98] But the science of Chemistry is unaffected thereby; the atoms

are not the ultimate units out of which material things are built, but

the atoms cannot be decomposed by purely chemical means; the “elements”

are not truly elemental, but _they are chemical elements_. However, the

atomic theory has been subjected to a far more searching criticism. Wald

argues that substances obey the law of definite proportions because of

the way in which they are prepared; chemists refuse, he says, to admit

any substance as a definite chemical compound unless it does obey this

law. Wald’s opinions have been supported by Professor Ostwald, who has

attempted to deduce the other stoichiometric laws on these grounds

without assuming any atomic hypothesis[99]; but these new ideas do not

appear to have gained the approval of chemists in general. It is not to

be supposed that chemists will give up without a struggle a mental tool

of such great utility as Dalton’s theory, in spite of its defects, has

proved itself to be. There does seem, however, to be logic in the

arguments of Wald and Ostwald, but the trend of recent scientific theory

and research does not appear to be in the direction of Wald’s views.

Certainly, however, it appears that, on the one hand, the atomic theory

is not necessitated by the so-called “stoichiometric laws”; but, on the

other hand, a molecular constitution of matter seems to be demanded by

the phenomenon known as the “Brownian Movement,” _i.e._, the

spontaneous, irregular and apparently perpetual movement of microscopic

portions of solid matter when immersed in a liquid medium; such movement

appearing to be explicable only as the result of the motion of the

molecules of which the liquid in question is built up.[100]

[98] For a critical examination of Materialism, the reader is

referred to the present writer’s _Matter, Spirit and the Cosmos_

(Rider, 1910), especially Chapters I. and IV.

[99] W. OSTWALD: “Faraday Lecture,” _Journal of the Chemical

Society_, vol. lxxxv. (1904), pp. 506 _et seq._ See also W. OSTWALD:

_The Fundamental Principles of Chemistry_ (translated by H. W.

Morse, 1909), especially Chapters VI., VII. and VIII.

[100] For an account of this singular phenomenon, see Prof. JEAN

PERRIN: _Brownian Movement and Molecular Reality_ (translated from

the _Annales de Chimie et de Physique_, 8me Séries, September, 1909,

by F. Soddy, M.A., F.R.S., 1910).

CHAPTER VII

MODERN ALCHEMY

“Modern Alchemy.”

§ =85.= Correctly speaking, there is no such thing as “Modern Alchemy”;

not that Mysticism is dead, or that men no longer seek to apply the

principles of Mysticism to phenomena on the physical plane, but they do

so after another manner from that of the alchemists. A new science,

however, is born amongst us, closely related on the one hand to

Chemistry, on the other to Physics, but dealing with changes more

profound and reactions more deeply seated than are dealt with by either

of these; a science as yet without a name, unless it be the not

altogether satisfactory one of “Radioactivity.” It is this science, or,

perhaps we should say, a certain aspect of it, to which we refer (it may

be fantastically) by the expression “Modern Alchemy”: the aptness of the

title we hope to make plain in the course of the present chapter.

X-rays and Becquerel rays.

§ =86.= As is commonly known, what are called X-rays are produced when

an electric discharge is passed through a high-vacuum tube. It has been

shown that these rays are a series of irregular pulses in the ether,

which are set up when the kathode particles strike the walls of the

glass vacuum tube,[101] and it was found that more powerful effects can

be produced by inserting a disc of platinum in the path of the kathode

particles. It was M. Becquerel who first discovered that there are

substances which naturally emit radiations similar to X-rays. He found

that uranium compounds affected a photographic plate from which they

were carefully screened, and he also showed that these uranium

radiations, or “Becquerel rays,” resemble X-rays in other particulars.

It was already known that certain substances fluoresce (emit light) in

the dark after having been exposed to sunlight, and it was thought at

first that the above phenomenon exhibited by uranium salts was of a like

nature, since certain uranium salts are fluorescent; but M. Becquerel

found that uranium salts which had never been exposed to sunlight were

still capable of affecting a photographic plate, and that this

remarkable property was possessed by all uranium salts, whether

fluorescent or not. This phenomenon is known as “radioactivity,” and

bodies which exhibit it are said to be “radioactive.” Schmidt found that

thorium compounds possess a similar property, and Professor Rutherford

showed that thorium compounds evolved also something resembling a gas.

He called this an “emanation.”

[101] They must not be confused with the greenish-yellow

phosphorescence which is also produced: the X-rays are invisible.

The Discovery of Radium.

§ =87.= Mme. Curie[102] determined the radioactivity of many uranium and

thorium compounds, and found that there was a proportion between the

radioactivity of such compounds and the quantity of uranium or thorium

in them, with the remarkable exception of certain natural ores, which

had a radioactivity much in excess of the normal, and, indeed, in

certain cases, much greater than pure uranium. In order to throw some

light on this matter, Mme. Curie prepared one of these ores by a

chemical process and found that it possessed a normal radioactivity. The

only logical conclusion to be drawn from these facts was that the ores

in question must contain some unknown, highly radioactive substance, and

the Curies were able, after very considerable labour, to extract from

pitchblende (the ore with the greatest radioactivity) minute quantities

of the salts of two new elements--which they named “Polonium” and

“Radium” respectively--both of which were extremely radioactive.

[102] See Madame SKLODOWSKA CURIE’S _Radio-active Substances_ (2nd

ed., 1904).

M. Debierne has obtained a third radioactive substance from pitchblende,

which he has called “Actinium.”

Chemical Properties of Radium.

§ =88.= Radium is an element resembling calcium, strontium, and barium

in chemical properties; its atomic weight was determined by Mme. Curie,

and found to be about 225, according to her first experiments; a

redetermination gave a slightly higher value, which has been confirmed

by a further investigation carried out by Sir T. E. Thorpe.[103] Radium

gives a characteristic spectrum, and is intensely radioactive. It

should be noted that up to the middle of the year 1910 the element

radium itself had not been prepared; in all the experiments carried out

radium salts were employed (_i.e._, certain compounds of radium with

other elements), generally radium chloride and radium bromide. In that

year, however, Mme. Curie, in conjunction with M. Debierne, obtained the

free metal. It is described as a white, shining metal resembling the

other alkaline earth metals. It reacts very violently with water, chars

paper with which it is allowed to come in contact, and blackens in the

air, probably owing to the formation of a nitride. It fuses at 700° C.,

and is more volatile than barium.[104]

[103] See Sir T. E. THORPE: “On the Atomic Weight of Radium”

(Bakerian Lecture for 1907. Delivered before the Royal Society, June

20, 1907), _Proceedings of the Royal Society of London_, vol. lxxx.

pp. 298 _et seq._; reprinted in _The Chemical News_, vol. xcvii. pp.

229 _et seq._ (May 15, 1908).

[104] Madame P. CURIE and M. A. DEBIERNE: “Sur le radium

métallique,” _Comptes Rendus hebdomadaires des Séances de l’Académie

des Sciences_, vol. cli. (1910), pp. 523-525. (For an English

translation of this paper see _The Chemical News_, vol. cii. p.

175.)

The Radioactivity of Radium.

§ =89.= Radium salts give off three distinct sorts of rays, referred to

by the Greek letters α, β, γ. The α-rays have been shown to consist of

electrically charged (positive) particles, with a mass approximately

equal to that of four hydrogen atoms; they are slightly deviated by a

magnetic field, and do not possess great penetrative power. The β-rays

are similar to the kathode rays, and consist of (negative) electrons;

they are strongly deviated by a magnetic field, in a direction opposite

to that in which the α-particles are deviated, and possess medium

penetrative power, passing for the most part through a thin sheet of

metal. The γ-rays resemble X-rays; they possess great penetrative

power, and are not deviated by a magnetic field. The difference in the

effect of the magnetic field on these rays, and the difference in their

penetrative power, led to their detection and allows of their separate

examination. Radium salts emit also an emanation, which tends to become

occluded in the solid salt, but can be conveniently liberated by

dissolving the salt in water, or by heating it. The emanation exhibits

the characteristic properties of a gas, it obeys Boyle’s Law (_i.e._,

its volume varies inversely with its pressure), and it can be condensed

to a liquid at low temperatures; its density as determined by the

diffusion method is about 100. Attempts to prepare chemical compounds of

the emanation have failed, and in this respect it resembles the rare

gases of the atmosphere--helium, neon, argon, krypton, and xenon--whence

it is probable that its molecules are monatomic, so that a density of

100 would give its atomic weight as 200.[105] As can be seen from the

table on pp. 106, 107, an atomic weight of about 220 corresponds to a

position in the column containing the rare gases in the periodic system.

That the emanation actually has an atomic weight of these dimensions was

confirmed by further experiments carried out by the late Sir William

Ramsay and Dr. R. W. Gray.[106] These chemists determined the density of

the emanation by actually weighing minute quantities of known volume of

the substance, sealed up in small capillary tubes, a specially

sensitive balance being employed. Values for the density varying from

108 to 113½, corresponding to values for the atomic weight varying from

216 to 227, were thereby obtained. Sir William Ramsay, therefore,

considered that there could no longer be any doubt that the emanation

was one of the elements of the group of chemically inert gases. He

proposed to call it _Niton_, and, for reasons which we shall note later,

considered that in all probability it had an atomic weight of about

222½.

[105] This follows from Avogadro’s Hypothesis, see § 76.

[106] Sir WILLIAM RAMSAY and Dr. R. W. GRAY: “La densité de

l’émanation du radium,” _Comptes Rendus hebdomadaires des Séances de

l’Académie des Sciences_, vol. cvi. (1910), pp. 126 _et seq._

The Disintegration of the Radium Atom.

§ =90.= Radium salts possess another very remarkable property, namely,

that of continuously emitting light and heat. It seemed, at first, that

here was a startling contradiction to the law of the conservation of

energy, but the whole mystery becomes comparatively clear in terms of

the corpuscular or the electronic theory of matter. The radium-atom is a

system of a large number (see § 81) of corpuscles or electrons, and

contains in virtue of their motion an enormous amount of energy. But it

is known from Chemistry that atomic systems (_i.e._, molecules) which

contain very much energy are unstable and liable to explode. The same

law holds good on the more interior plane--the radium-atom is liable to,

and actually does, explode. And the result? Energy is set free, and

manifests itself partly as heat and light. Some free electrons are shot

off (the β-rays), which, striking the undecomposed particles of salt,

give rise to pulses in the ether (the γ-rays),[107] just as the kathode

particles give rise to X-rays when they strike the walls of the vacuum

tube or a platinum disc placed in their path. The β- and γ-rays do not,

however, result immediately from the exploding radium-atoms, the initial

products being the emanation and one α-particle from each radium-atom

destroyed.

[107] This view regarding the γ-rays is not, however, universally

accepted, some scientists regarding them as consisting of a stream

of particles moving with very high velocities.

“Induced Radioactivity.”

§ =91.= Radium salts have the property of causing surrounding objects to

become temporally radioactive. This “induced radioactivity,” as it may

be called, is found to be due to the emanation, which is itself

radioactive (it emits α-rays only), and is decomposed into minute traces

of solid radioactive deposits. By examining the rate of decay of the

activity of the deposit, it has been found that it is undergoing a

series of sub-atomic changes, the products being termed Radium A, B, C,

&c. It has been proved that all the β- and γ-rays emitted by radium

salts are really due to certain of these secondary products. Radium F is

thought to be identical with Polonium (§ 87). Another product is also

obtained by these decompositions, with which we shall deal later (§ 94).

Properties of Uranium and Thorium.

§ =92.= Uranium and thorium differ in one important respect from radium,

inasmuch as the first product of the decomposition of the uranium and

thorium atoms is in both cases solid. Sir William Crookes[108] was able

to separate from uranium salts by chemical means a small quantity of an

intensely radioactive substance, which he called Uranium X, the residual

uranium having lost most of its activity; and M. Becquerel, on

repeating the experiment, found that the activity of the residual

uranium was slowly regained, whilst that of the uranium X decayed. This

is most simply explained by the theory that uranium first changes into

uranium X. It has been suggested that radium may be the final product of

the breaking up of the uranium-atom; at any rate, it is quite certain

that radium must be evolved in some way, as otherwise there would be

none in existence--it would all have decomposed. This suggestion has

been experimentally confirmed, the growth of radium in large quantities

of a solution of purified uranyl nitrate having been observed. Uranium

gives no emanation. Thorium probably gives at least three solid

products--Meso-thorium, Radio-thorium, and Thorium X, the last of which

yields an emanation resembling that obtained from radium, but not

identical with it.

[108] Sir WILLIAM CROOKES, F.R.S.: “Radio-activity of Uranium,”

_Proceedings of the Royal Society of London_, vol. lxvi. (1900), pp.

409 _et seq._

The Radium Emanation.

§ =93.= We must now more fully consider the radium emanation--a

substance with more astounding properties than even the radium compounds

themselves. By distilling off the emanation from some radium bromide,

and measuring the quantities of heat given off by the emanation and the

radium salt respectively, Professors Rutherford and Barnes[109] proved

that nearly three-fourths of the total amount of heat given out by a

radium salt comes from the minute quantity of emanation that it

contains. The amount of energy liberated as heat during the decay of the

emanation is enormous; one cubic centimetre liberates about four

million times as much heat as is obtained by the combustion of an equal

volume of hydrogen. Undoubtedly this must indicate some profound change,

and one may well ask, What is the ultimate product of the decomposition

of the emanation?

[109] E. RUTHERFORD, F.R.S., and H. T. BARNES, D.Sc.: “Heating

Effect of the Radium Emanation,” _Philosophical Magazine_ [6], vol.

vii. (1904), pp. 202 _et seq._

The Production of Helium from Radium.

§ =94.= It had been observed already that the radioactive minerals on

heating give off Helium--a gaseous element, characterised by a

particular yellow line in its spectrum--and it seemed not unlikely that

helium might be the ultimate decomposition product of the emanation. A

research to settle this point was undertaken by Sir William Ramsay and

Mr. Soddy,[110] and a preliminary experiment having confirmed the above

speculation, they carried out further very careful experiments. “The

maximum amount of the emanation obtained from 50 milligrams of radium

bromide was conveyed by means of oxygen into a [U]-tube cooled in liquid

air, and the latter was then extracted by the pump.” The spectrum was

observed; it “was apparently a new one, probably that of the emanation

itself. . . . After standing from July 17 to 21 the helium spectrum

appeared, and the characteristic lines were observed.” Sir William

Ramsay performed a further experiment with a similar result, in which

the radium salt had been first of all heated in a vacuum for some time,

proving that the helium obtained could not have been occluded in it;

though the fact that the helium spectrum did not immediately appear, in

itself proves this point. Sir William Ramsay’s results were confirmed

by further careful experiments by Sir James Dewar and other chemists. It

was suggested, therefore, that the α-particle consists of an

electrically charged helium-atom, and not only is this view in agreement

with the value of the mass of this particle as determined

experimentally, but it has been completely demonstrated by Professor

Rutherford and Mr. Royds. These chemists performed an experiment in

which the emanation from about one-seventh of a gramme of radium was

enclosed in a thin-walled tube, through the walls of which the

α-particles could pass, but which were impervious to gases. This tube

was surrounded by an outer jacket, which was evacuated. After a time the

presence of helium in the space between the inner tube and the outer

jacket was observed spectroscopically.[111] Now, the emanation-atom

results from the radium-atom by the expulsion of one α-particle; and

since this latter consists of an electrically charged helium-atom, it

follows that the emanation must have an atomic weight of 226 - 4,

_i.e._, 222. This value is in agreement with Sir William Ramsay’s

determination of the density of the emanation. We may represent the

degradation of the radium-atom, therefore, by the following scheme:--

α-particle (Helium-atom)

/ 4

Radium-atom α-particle (Helium-atom)

226 \ / 4

Emanation (Niton-atom)

222 \

Radium-A, &c.

[110] Sir WILLIAM RAMSAY and FREDERICK SODDY: “Experiments in

Radioactivity and the Production of Helium from Radium,”

_Proceedings of the Royal Society of London_, vol. lxxii. (1903),

pp. 204 _et seq._

[111] E. RUTHERFORD, F.R.S., and T. ROYDS, M.Sc.: “The Nature of the

α-Particle from Radio-active Substances,” _Philosophical Magazine_

[6], vol. xvii. (1909), pp. 281 _et seq._

Nature of this Change.

§ =95.= Here, then, for the first time in the history of Chemistry, we

have the undoubted formation of one chemical element from another, for,

leaving out of the question the nature of the emanation, there can be no

doubt that radium is a chemical element. This is a point which must be

insisted upon, for it has been suggested that radium may be a compound

of helium with some unknown element; or, perhaps, a compound of helium

with lead, since it has been shown that lead is probably one of the end

products of the decomposition of radium. The following considerations,

however, show this view to be altogether untenable: (i.) All attempts to

prepare compounds of helium with other elements have failed. (ii.)

Radium possesses all the properties of a chemical element; it has a

characteristic spectrum, and falls in that column in the Periodic Table

with those elements which it resembles as to its chemical properties.

(iii.) The quantity of heat liberated on the decomposition of the

emanation is, as we have already indicated, out of all proportion to

that obtained even in the most violent chemical reactions; and (iv.) one

very important fact has been observed, namely, that the rate of decay of

the emanation is unaffected by even extreme changes of temperature,

whereas chemical actions are always affected in rate by changes of

temperature. It will also be advisable, perhaps, to indicate some of the

differences between helium and the emanation. The latter is a heavy gas,

condensable to a liquid by liquid air (recently it has been

solidified[112]); whereas helium is the lightest of all known gases

with the exception of hydrogen and has been liquefied only by the most

persistent effort.[113] The emanation, moreover, is radioactive, giving

off α-particles, whereas helium does not possess this property.

[112] By Ramsay. See _Proceedings of the Chemical Society_, vol.

xxv. (1909), pp. 82 and 83.

[113] By Professor Onnes. See _Chemical News_, vol. xcviii. p. 37

(July 24, 1908).

Is this Change a true Transmutation?

§ =96.= It has been pointed out, however, that (in a sense) this change

(viz., of emanation into helium) is not quite what has been meant by the

expression “transmutation of the elements”; for the reason that it is a

_spontaneous_ change; no effort of ours can bring it about or cause it

to cease.[114] But the fact of the change does go to prove that the

chemical elements are not the discrete units of matter that they were

supposed to be. And since it appears that all matter is radioactive,

although (save in these exceptional cases) in a very slight degree,[115]

we here have evidence of a process of evolution at work among the

chemical elements. The chemical elements are not permanent; they are all

undergoing change; and the common elements merely mark those points

where the rate of the evolutionary process is at its slowest. (See also

§§ 78 and 83.) Thus, the essential truth in the old alchemistic doctrine

of the growth of metals is vindicated, for the metals do grow in the

womb of Nature, although the process may be far slower than appears to

have been imagined by certain of the alchemists,[116] and although gold

may not be the end product. As writes Professor Sir W. Tilden: “. . . It

appears that modern ideas as to the genesis of the elements, and hence

of all matter, stand in strong contrast with those which chiefly

prevailed among experimental philosophers from the time of Newton, and

seem to reflect in an altered form the speculative views of the

ancients.” “. . . It seems probable,” he adds, “that the chemical

elements, and hence all material substances of which the earth, the sea,

the air, and the host of heavenly bodies are all composed, resulted from

a change, corresponding to condensation, in something of which we have

no direct and intimate knowledge. Some have imagined this primal essence

of all things to be identical with the ether of space. As yet we know

nothing with certainty, but it is thought that by means of the

spectroscope some stages of the operation may be seen in progress in the

nebulæ and stars. . . .”[117] We have next to consider whether there is

any experimental evidence showing it to be possible (using the

phraseology of the alchemists) for man to assist in Nature’s work.

[114] See Professor H. C. JONES: _The Electrical Nature of Matter

and Radioactivity_ (1906), pp. 125-126.

[115] It has been definitely proved, for example, that the common

element potassium is radioactive, though very feebly so (it emits

β-rays). It is also interesting to note that many common substances

emit corpuscles at high temperatures.

[116] Says Peter Bonus, however, “. . . we know that the generation

of metals occupies thousands of years . . . in Nature’s workshop.

. . .” (see _The New Pearl of Great Price_, Mr. A. E. Waite’s

translation, p. 55), and certain others of the alchemists expressed

a similar view.

[117] Sir WILLIAM A. TILDEN: _The Elements: Speculations as to their

Nature and Origin_ (1910), pp. 108, 109, 133 and 134. With regard to

Sir William Tilden’s remarks, it is very interesting to note that

Swedenborg (who was born when Newton was between forty and fifty

years old) not only differed from that great philosopher on those

very points on which modern scientific philosophy is at variance

with Newton, but, as is now recognised by scientific men,

anticipated many modern discoveries and scientific theories. It

would be a most interesting task to set forth the agreement existing

between Swedenborg’s theories and the latest products of scientific

thought concerning the nature of the physical universe. Such,

however, would lie without the confines of the present work.

The Production of Neon from Emanation.

§ =97.= As we have already indicated above (§ 93), the radium emanation

contains a vast store of potential energy, and it was with the idea of

utilising this energy for bringing about chemical changes that Sir

William Ramsay[118] undertook a research on the chemical action of this

substance--a research with the most surprising and the most interesting

results, for the energy contained within the radium emanation appeared

to behave like a veritable Philosopher’s Stone. The first experiments

were carried out on distilled water. It had already been observed that

the emanation decomposes water into its gaseous elements, oxygen and

hydrogen, and that the latter is always produced in excess. These

results were confirmed and the presence of hydrogen peroxide was

detected, explaining the formation of an excess of hydrogen; it was also

shown that the emanation brings about the reverse change to some extent,

causing oxygen and hydrogen to unite with the production of water, until

a position of equilibrium is attained. On examining spectroscopically

the gas obtained by the action of the emanation on water, after the

removal of the ordinary gases, a most surprising result was

observed--the gas showed a brilliant spectrum of neon, accompanied with

some faint helium lines. A more careful experiment was carried out later

by Sir William Ramsay and Mr. Cameron, in which a silica bulb was

employed instead of glass. The spectrum of the residual gas after

removing ordinary gases was successfully photographed, and a large

number of the neon lines identified; helium was also present. The

presence of neon could not be explained, in Ramsay’s opinion, by leakage

of air into the apparatus, as the percentage of neon in the air is not

sufficiently high, whereas this suggestion might be put forward in the

case of argon. Moreover, the neon could not have come from the aluminium

of the electrodes (in which it might be thought to have been occluded),

as the sparking tube had been used and tested before the experiment was

carried out. The authors conclude: “We must regard the transformation of

emanation into neon, in presence of water, as indisputably proved, and,

if a transmutation be defined as a transformation brought about at will,

by change of conditions, then _this is the first case of transmutation

of which conclusive evidence is put forward_.”[119] However, Professor

Rutherford and Mr. Royds have been unable to confirm this result. They

describe[120] attempts to obtain neon by the action of emanation on

water. Out of five experiments no neon was obtained, save in one case in

which a small air leak was discovered; and, since the authors find that

very minute quantities of this gas are sufficient to give a clearly

visible spectrum, they conclude that Ramsay’s positive results are due,

after all, to leakage of air into the apparatus. But if this is the true

explanation of Ramsay’s results, it is difficult to understand why, in

the case of the experiment with a solution of a copper salt described

below, the presence of neon was not detected, for, if due to leakage,

the proportions of the rare gases present should presumably have been

the same in all the experiments. Further research seems necessary

conclusively to settle the question.

[118] Sir WILLIAM RAMSAY: “The Chemical Action of the Radium

Emanation. Pt. I., Action on Distilled Water,” _Journal of the

Chemical Society_, vol. xci. (1907), pp. 931 _et seq._ ALEXANDER T.

CAMERON and Sir WILLIAM RAMSAY, _ibid._ “Pt. II., On Solutions

containing Copper, and Lead, and on Water,” _ibid._ pp. 1593 _et

seq._ “Pt. III., On Water and Certain Gases,” _ibid._ vol. xciii.

(1908), pp. 966 _et seq._ “Pt. IV., On Water,” _ibid._ pp. 992 _et

seq._

[119] _Journal of the Chemical Society_, vol. xciii. (1908), p. 997.

[120] E. RUTHERFORD, F.R.S., and T. ROYDS, M.Sc.: “The Action of

Radium Emanation on Water,” _Philosophical Magazine_ [6], vol. xvi.

(1908), pp. 812 _et seq._

Ramsay’s Experiments on Copper.

§ =98.= The fact that an excess of hydrogen was produced when water was

decomposed by the emanation suggested to Sir William Ramsay and Mr.

Cameron that if a solution of a metallic salt was employed in place of

pure water, the free metal might be obtained. These “modern alchemists,”

therefore, proceeded to investigate the action of radium emanation on

solutions of copper and lead salts, and again apparently effected

transmutations. They found on removing the copper from a solution of a

copper-salt which had been subjected to the action of the emanation, and

spectroscopically examining the residue, that a considerable quantity of

sodium was present, together with traces of lithium; and the gas evolved

in the case of a solution of copper nitrate contained, along with much

nitric oxide and a little nitrogen, argon (which was detected

spectroscopically), but no helium. It certainly seemed like a dual

transformation of copper into lithium and sodium, and emanation into

argon. They also observed that apparently carbon-dioxide is continually

evolved from an acid solution of thorium nitrate (see below, § 100). It

is worth while noticing that helium, neon and argon occur in the same

column in the Periodic Table with emanation; lithium and sodium with

copper, and carbon with thorium; in each case the elements produced

being of lighter atomic weight than those decomposed.[121] The authors

make the following suggestions: “(1) That helium and the α-particle are

not identical; (2) that helium results from the ‘degradation’ of the

large molecule of emanation by its bombardment with α-particles; (3)

that this ‘degradation,’ when the emanation is alone or mixed with

oxygen and hydrogen, results in the lowest member of the inactive

series, namely, helium; (4) that if particles of greater mass than

hydrogen or oxygen are associated with the emanation, namely, liquid

water, then the ‘degradation’ of the emanation is less complete, and

neon is produced; (5) that when molecules of still greater weight and

complexity are present, as is the case when the emanation is dissolved

in a solution of copper sulphate, the product of ‘degradation’ of the

emanation is argon. We are inclined to believe too [they say] that (6)

the copper also is involved in this process of degradation, and is

reduced to the lowest term of its series, namely, lithium; and at the

same time, inasmuch as the weight of the residue of alkali, produced

when copper nitrate is present, is double that obtained from the blank

experiment, or from water alone, the supposition is not excluded that

the chief product of the ‘degradation’ of copper is sodium.”[122]

[121] See pp. 106, 107.

[122] _Journal of the Chemical Society_, vol. xci. (1907), pp.

1605-1606. More recent experiments, however, proved that the

α-particle does consist of an electrically charged helium-atom, and

this view was latterly accepted by Sir William Ramsay, so that the

above suggestions must be modified in accordance therewith. (See §

94.)

Further Experiments on Radium and Copper.

§ =99.= A little later Madame Curie and Mademoiselle Gleditsch[123]

repeated Cameron and Ramsay’s experiments on copper salts, using,

however, platinum apparatus. They failed to detect lithium after the

action of the emanation, and think that Cameron and Ramsay’s results may

be due to the glass vessels employed. Dr. Perman[124] has investigated

the direct action of the emanation on copper and gold, and has failed to

detect any trace of lithium. The transmutation of copper into lithium,

therefore, must be regarded as unproved, but further research is

necessary before any conclusive statements can be made on the subject.

[123] Madame CURIE and Mademoiselle GLEDITSCH: “Action de

l’émanation du radium sur les solutions des sels de cuivre,”

_Comptes Rendus hebdomadaires des Séances de l’Académie des

Sciences_, vol. cxlvii. (1908), pp. 345 _et seq._ (For an English

translation of this paper, see _The Chemical News_, vol. xcviii. pp.

157 and 158.)

[124] EDGAR PHILIP PERMAN: “The Direct Action of Radium on Copper

and Gold,” _Proceedings of the Chemical Society_, vol. xxiv. (1908),

p. 214.

Ramsay’s Experiments on Thorium and allied Metals.

§ =100.= In his presidential address to the Chemical Society, March 25,

1909, after having brought forward some exceedingly interesting

arguments for the possibility of transmutation, Sir William Ramsay

described some experiments which he had carried out on thorium and

allied elements.[125] It was found, as we have already stated (§ 98),

that, apparently, carbon-dioxide was continually evolved from an acid

solution of thorium nitrate, precautions being taken that the gas was

not produced from the grease on the stop-cock employed, and it also

appeared that carbon-dioxide was produced by the action of radium

emanation on thorium nitrate. The action of radium emanation on

compounds (not containing carbon) of other members of the carbon group,

namely, silicon, zirconium and lead, was then investigated; in the cases

of zirconium nitrate and hydro-fluosilicic acid, carbon-dioxide was

obtained; but in the case of lead chlorate the amount of carbon dioxide

was quite insignificant. Curiously enough, the perchlorate of bismuth, a

metal which belongs to the nitrogen group of elements, also yielded

carbon-dioxide when acted on by emanation. Sir William Ramsay concludes

his discussion of these experiments as follows: “Such are the facts. No

one is better aware than I how insufficient the proof is. Many other

experiments must be made before it can confidently be asserted that

certain elements, when exposed to ‘concentrated energy,’ undergo

degradation into carbon.” Some such confirmatory experiments were

carried out by Sir William Ramsay and Mr. Francis L. Usher, and they

also described an experiment with a compound of titanium. Their results

confirm Sir William Ramsay’s former experiments. Carbon-dioxide was

obtained in appreciable quantities by the action of emanation on

compounds of silicon, titanium, zirconium and thorium. In the case of

lead, the amount of carbon dioxide obtained was inappreciable.[126]

[125] Sir WILLIAM RAMSAY: “Elements and Electrons,” _Journal of the

Chemical Society_, vol. xcv. (1909), pp. 624 _et seq._

[126] For a brief account in English of these later experiments see

_The Chemical News_, vol. c. p. 209 (October 29, 1909).

The Possibility of Making Gold.

§ =101.= It does not seem unlikely that if it is possible to “degrade”

elements, it may be possible to build them up. It has been suggested

that it might be possible to obtain, in this way, gold from silver,

since these two elements occur in the same column in the Periodic Table;

but the suggestion still awaits experimental confirmation. The question

arises, What would be the result if gold could be cheaply produced? That

gold is a metal admirably adapted for many purposes, for which its

scarcity prevents its use, must be admitted. But the financial chaos

which would follow if it were to be cheaply obtained surpasses the

ordinary imagination. It is a theme that ought to appeal to a novelist

of exceptional imaginative power. However, we need not fear these

results, for not only is radium extremely rare, far dearer than gold,

and on account of its instability will never be obtained in large

quantities, but, judging from the above-described experiments, if,

indeed, the radium emanation is the true Philosopher’s Stone, the

quantity of gold that may be hoped for by its aid is extremely small.

The Significance of “Allotropy.”

§ =102.= A very suggestive argument for the transmutation of the metals

was put forward by Professor Henry M. Howe, LL.D., in a paper entitled

“Allotropy or Transmutation?” read before the British Association

(Section B), Sheffield Meeting, 1910. Certain substances are known

which, although differing in their physical properties very markedly,

behave chemically as if they were one and the same element, giving rise

to the same series of compounds. Such substances, of which we may

mention diamond, graphite and charcoal (_e.g._, lampblack)--all of which

are known chemically as “carbon”--or, to take another example, yellow

phosphorus (a yellow, waxy, highly inflammable solid) and red phosphorus

(a difficultly-inflammable, dark red substance, probably possessing a

minutely crystalline structure), are, moreover, convertible one into the

other.[127] It has been customary to refer to such substances as

different forms or allotropic modifications of the same element, and not

to regard them as being different elements. As Professor Howe says, “If

after defining ‘elements’ as substances hitherto indivisible, and

different elements as those which differ in at least some one property,

and after asserting that the elements cannot be transmuted into each

other, we are confronted with the change from diamond into lampblack,

and with the facts, first, that each is clearly indivisible hitherto

and hence an element, and, second, that they differ in every property,

we try to escape in a circle by saying that they are not different

elements because they do change into each other. In short, we limit the

name ‘element’ to indivisible substances which cannot be transmuted into

each other, and we define those which do transmute as _ipso facto_ one

element, and then we say that the elements cannot be transmuted. Is not

this very like saying that, if you call a calf’s tail a leg, then a calf

has five legs? And if it is just to reply that calling a tail a leg does

not make it a leg, is it not equally just to reply that calling two

transmutable elements one element does not make them so?

[127] Diamond is transformed into graphite when heated by a powerful

electric current between carbon poles, and both diamond and graphite

can be indirectly converted into charcoal. The artificial production

of the diamond, however, is a more difficult process; but the late

Professor Moissan succeeded in effecting it, so far as very small

diamonds are concerned, by dissolving charcoal in molten iron or

silver and allowing it to crystallise from the solution under high

pressure. Graphite was also obtained. Red phosphorus is produced

from yellow phosphorus by heating the latter in absence of air. The

temperature 240-250° C. is the most suitable; at higher temperatures

the reverse change sets in, red phosphorus being converted into

yellow phosphorus.

“Is it philosophical to point to the fact that two such transmutable

elements yield but a single line of derivatives as proof that they are

one element? Is not this rather proof of the readiness, indeed

irresistibleness, of their transmutation? Does not this simply mean that

the derivativeless element, whenever it enters into combination,

inevitably transmutes into its mate which has derivatives?”[128]

[128] Professor HENRY M. HOWE, LL.D.: “Allotropy or Transmutation.”

(See _The Chemical News_, vol. cii. pp. 153 and 154, September 23,

1910.)

According to the atomic theory the differences between what are termed

“allotropic modifications” are generally ascribed to differences in the

number and arrangement of the atoms constituting the molecules of such

“modifications,” and not to any differences in the atoms themselves. But

we cannot argue that two such “allotropic modifications” or elements

which are transmutable into one another are one and the same element,

because they possess the same atomic weight, and different elements are

distinguished by different atomic weights; for the reason that, in the

determination of atomic weights, derivatives of such bodies are

employed; hence, the value obtained is the atomic weight of the element

which forms derivatives, from which that of its derivativeless mate may

differ considerably for all we know to the contrary, if we do, indeed,

regard the atomic weights of the elements as having any meaning beyond

expressing the inertia-ratios in which they combine one with another.

If we wish to distinguish between two such “allotropic modifications”

apart from any theoretical views concerning the nature and constitution

of matter, we can say that such “modifications” are different because

equal weights of them contain, or are equivalent to, different

quantities of energy,[129] since the change of one “form” to another

takes place only with the evolution or absorption (as the case may be)

of heat.[130] But, according to modern views regarding the nature of

matter, this is the sole fundamental difference between two different

elements--such are different because equal weights of them contain or

are equivalent to different quantities of energy. The so-called

“allotropic modifications of an element,” therefore, are just as much

different elements as any other different elements, and the change from

one “modification” to another is a true transmutation of the elements;

the only distinction being that what are called “allotropic

modifications of the same element” differ only slightly in respect of

the energy they contain, and hence are comparatively easy to convert one

into the other, whereas different elements (so called) differ very

greatly from one another in this respect, whence it is to be concluded

that the transmutation of one such element into another will only be

attained by the utilisation of energy in a very highly concentrated

form, such as is evolved simultaneously with the spontaneous

decomposition of the radium emanation.

[129] For a defence of the view that chemical substances may be

regarded as energy-complexes, and that this view is equally as valid

as the older notion of a chemical substance as an inertia-complex,

_i.e._, as something made up entirely of different units or atoms

each characterised by the possession of a definite and constant

weight at a fixed point on the earth’s surface, see an article by

the present writer, entitled “The Claims of Thermochemistry,”

_Knowledge and Scientific News_, vol. vii. (New Series), pp. 227 _et

seq._ (July, 1910).

[130] In some cases the heat change accompanying the transformation

of an element into an “allotropic modification” can be measured

directly. More frequently, however, it is calculated as the

difference between the quantities of heat obtained when the two

“forms” are converted into one and the same compound.

Conclusion.

§ =103.= We have shown that modern science indicates the essential truth

of alchemistic doctrine, and our task is ended. Writing in 1904, Sir

William Ramsay said: “If these hypotheses [concerning the possibility of

causing the atoms of ordinary elements to absorb energy] are just, then

the transmutations of the elements no longer appears an idle dream. The

philosopher’s stone will have been discovered, and it is not beyond the

bounds of possibility that it may lead to that other goal of the

philosophers of the dark ages--the _elixir vitæ_. For the action of

living cells is also dependent on the nature and direction of the energy

which they contain; and who can say that it will be impossible to

control their action, when the means of imparting and controlling energy

shall have been investigated?”[131] Whatever may be the final verdict

concerning his own experiments, those of Sir Ernest Rutherford, referred

to in the Preface to the present edition, demonstrate the fact of

transmutation; and it is worth noticing how many of the alchemists’

obscure descriptions of their Magistery well apply to that marvellous

something which we call Energy, the true “First Matter” of the Universe.

And of the other problem, the _Elixir Vitæ_, who knows?

[131] Sir WILLIAM RAMSAY: “Radium and its Products,” _Harper’s

Magazine_ (December 1904), vol. xlix. (European Edition), p. 57.

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Transcriber’s Notes:

The text of the original work has been retained, including

inconsistencies in spelling, hyphenation, punctuation, etc., except

as mentioned below.

Page 82, footnote [85]: the original work had a letter missing; “or”

seems to fit best (or van Helmont’s Workes).

Page 84, Memnonite: possibly error for Mennonite.

Page 93, fulfull: possibly error for fulfill.

Changes made to the text:

Footnotes and illustrations have been moved outside text paragraphs.

Some minor obvious typographical and punctuation errors have been

corrected silently.

Page xvii: 142 changed to 140 (Table of Contents)

Page 10: quesable changed to questionable

Page 41: Trismegistus changed to Trismegistos as elsewhere

Page 66: Gentlemen changed to Gentleman

Page 120, footnote [104]: Séances l’Académie changed to Séances de

l’Académie

Page 140, footnote [130]: modication changed to modification.

End of Project Gutenberg's Alchemy: Ancient and Modern, by H. Stanley Redgrove

Alchemy: Ancient and Modern Being a Brief Account of the Alchemistic Doctrines, and Their Relations, to Mysticism on the One Hand, and to Recent Discoveries in Physical Science on the Other Hand; Together with Some Particulars Regarding the Lives and Teachings of the Most Noted Alchemists · 第 9 / 9 章

§ =73.= Robert Boyle (1626-1691) had defined an element as a substance