PART II

We have now made a rapid survey of the history of chemistry, and traced the evolution of thought which has rendered possible the newer conceptions of the constitution of matter. We must now say a few words as to the nature of the various elements themselves, and give a brief account of some modern researches. A few practical hints as to experiments may also be of interest to the reader.

We have seen that when two chemical elements combine, some third substance is formed, quite different in properties from the original two. Thus, water seems to us entirely different from the two invisible gases which compose it--oxygen and hydrogen. Yet a simple experiment will prove that such is the case. We can decompose water by means of an electric current, when the original gases are given off, in the proportion of two to one--hydrogen collecting at the negative pole, and oxygen at the positive. This process can be kept up until all the water has been decomposed, and only hydrogen and oxygen gases remain. This process of electrical decomposition is known as _electrolysis_.

THE ELEMENTS

_Hydrogen_ is the lightest of all gases, and, as we have seen, the simplest of the elements, in its constitution. Like all gases, it can be liquefied, and even frozen solid into a hard lump, like ice. On the other hand, even the densest of substances can be liquefied, and even turned into gas or vapor at a sufficiently high temperature. (Gases are rendered liquid or solid at a very low temperature.) Liquid air, for example, is so cold that when a can of it is set upon a block of ice the liquid air boils and gives off “steam”!

_Oxygen_ gas constitutes about one-fifth of our atmospheric air (the other four parts being nitrogen) and is the most essential element in supporting life. Without it, life would at once become extinct. All forms of combustion take place very rapidly in oxygen, and the combustion going on within the human body is no exception to this rule. The atmospheric nitrogen acts as a sort of dilutant, being an inert gas. If a mouse be placed under a jar of pure oxygen gas, it will often run round and round until it drops dead with exhaustion. In an atmosphere of pure oxygen, we should soon burn up, and live our lives too rapidly.

Oxygen has a great tendency to combine with various other elements, particularly metals. Thus, iron rust is due to the combination of oxygen with iron; the blackening and tarnishing of cooking pots is due to the slow oxidation of copper, etc.

In breathing, we take in oxygen from the air, which combines with the gases in the lungs, forming carbon dioxide. Curiously enough, plants thrive upon this gas, which is so poisonous to human beings, and in turn give off oxygen. Hence the value of plants and flowers in the room, or in any densely inhabited area.

_Nitrogen_ is a very important element, entering into many chemical combinations. It forms the basis of explosives, used in war. Until relatively recently, this element had to be obtained from substances dug out of the ground, but during the late war, methods were devised for obtaining it from the air. “Nitrogen fixation” became possible. If it had not been for this discovery, Germany would have had to give up the war in 1916, at the latest.

Nitrogen combines with hydrogen, to form ammonia; with oxygen and water, to form nitric acid; with nitric acid and potash to form gunpowder, etc.

Certain oxides combine with water, to form what are known as _bases_. Bases can combine with acids, giving rise to _salts_.

_Carbon_ is an essential element for all living matter; it combines with oxygen, to yield carbonic acid; with hydrogen, giving rise to a great number of compounds, such as benzene, turpentine, etc. Marsh gas, illuminating gas, acetylene, etc., are compounds of carbon.

_Chlorine_ is a very important element, combining with sodium to form common salt. As we have seen, the saltness of the sea is due to this substance. Owing to its great affinity for hydrogen, chlorine decomposes water, setting free oxygen. The result of this is that a mixture of chlorine and water has strong bleaching qualities.

Chlorine also combines with hydrogen to form hydrochloric acid. On the other hand, it shows little sympathy for oxygen, forming but few stable compounds. Chloroform, so long useful in surgical anaesthesia, is a compound of chlorine, carbon and hydrogen.

_Sulphur_ can assume a variety of appearances (allotrophic variation) as we have seen. Sulphuric acid, etc., are its compounds. The latter substance is used for bleaching violets, but the flowers become violet again when put into an ammonia solution.

_Sodium_ is a metal, which burns when thrown into water. It is the other constituent of common salt, and enters into a great variety of combinations. Carbonate of soda is one of these.

Many of the elements--iron, nickel, gold, platinum, silver, etc.,--are too well known to necessitate more than a brief note. It is interesting to notice, however, that there are certain “family relations” among a number of the elements. Thus, sodium and potassium are “related”; and so are barium, strontium and calcium. Again, oxygen and sulphur have a number of points in common,--although one is a solid and the other a gas! Gold stands rather apart from the rest.

Two very interesting groups should be mentioned in this place. The first is the group of _rare gases_--argon, neon, etc.,--most of which have been discovered only recently. They are inert, and partly on account of this, and partly on account of their rarity, their discovery was so long delayed.

RADIO-ACTIVITY

The second list is the _radio-active_ group of elements,--uranium, radium, thorium, actinium, etc. These all possess their characteristic properties in varying degrees,--giving off alpha, beta and gamma rays. A certain mysterious “emanation” is also emitted by radio-active elements, but the study of these rays and their influence would take us into the realm of “physics,” and would more properly belong to a book on physics than in the present, dealing with chemistry.

One very interesting fact should, however, be mentioned in this connection, and that is the evolution of matter which has been observed, as the result of spectrum analysis. We have heard much of organic evolution, meaning the evolution of life upon our planet. It is equally true that there is an inorganic evolution, in which the gradual development of chemical elements may similarly be traced. Thus, it has been noticed that, in the hottest stars, (gaseous) the fewest chemical elements exist; in those of medium temperature (metallic), more elements are found, while in those having the lowest temperature (carbon stars) the greatest number of chemical elements are to be distinguished. This seems to prove that the higher the temperature, the fewer the elements, which in turn leads to the conclusion that all elements are perhaps ultimately ONE--as Sir William Crookes suggested many years ago. As these stars cool, more and more elements seem to be “crystallized out,” so to say,--the many being formed from the fewer. The newer researches on the constitution of matter render this idea all the more plausible.

THE ORIGIN OF LIFE

Just here, it might be well to point out the late place occupied by life, in this process of inorganic evolution. The Absolute Zero of inter-stellar space is about -273°C. On the other hand, the temperature of the hottest stars is more than 30,000°! (Argo, Alnitam, etc.) The temperature must fall from this to a few degrees above Zero (the boiling point of water), before life can become manifest at all. Life as we know it can only exist between the boiling and the freezing points of water. This point is only reached towards the very end of the scale. It has therefore been said that, cosmically speaking, life is only a “flash in the pan between two eternities”--but for us that flash in the pan is everything!

The question of the origin of life upon our planet has been discussed at some length in my little book on “Life: Its Origin and Nature,” in the present series. It may be of interest to mention here, however, a few of the experiments which have been made upon the artificial creation of life, by means of inorganic chemicals, since these properly fall into place in a book devoted to chemistry.

Dr. H. Charlton Bastian, of England, conducted many years ago a series of experiments of this character, in which he claimed to have made living matter from sterilized chemicals. He placed these in a glass bottle which had been sterilized, heated the contents until steam issued from the mouth of the flask, and then instantly sealed up the bottle, preventing the entrance of air. The flasks were then put away for several days, and at the end of that time were found, upon examination, to contain living organisms.

“CREATION” OF LIFE

The reader will probably be interested in knowing the precise chemical formulæ employed for obtaining these astonishing results. Several such formulæ are given in Dr. Bastian’s book, “The Evolution of Life,” of which the following are samples:

Sodium silicate, two, or three, drops. Ammonium phosphate, four, or six, grains. Dilute phosphoric acid, four, or six, drops. Distilled water, one fluid ounce.

Another formula is the following:

Sodium silicate, three drops. Liquor ferri pernitratis, eight drops. Distilled water, one fluid ounce.

The reader can try the experiment for himself. It should be said, however, that although Dr. Bastian’s results were undoubted, they failed to carry conviction to the scientific world as a whole, since they contended that some experimental error must have crept in, to render these results possible; and it is significant, in this connection, that the same experiments repeated by other men failed to yield the same striking results.

Chemistry, then, enters into practically every field of inquiry--the constitution of human beings, no less than that of metals, earths or distant nebulæ. Everything material in the Universe is composed of elements, of atoms, and these atoms are built-up, as we have seen, of electrons, which are not matter at all, but bundles of energy. No two particles of matter in the world actually touch, or come near to touching one another. It is an interesting thought, when one stops to think of it that, for instance, the steel pillar supporting a “sky-scraper,” upon which rests an enormous weight (the whole of the superstructure) is not really dense and solid, as it appears, but is actually tenuous and shadowy, and that no two of its atoms ever touch one another; they are separated by relatively vast spaces, filled only with the hypothetical “ether.” The whole weight of the building may be said to rest upon nothing,--or at most upon ether, which thus bears its strain!

THE ETHER

And what is this ether? Is it matter in some subtle form, or is it something else? We do not know; certainly it is no form of matter known to us, and its reality has even been called into question of late. Hæckel, as we know, contended (“The Riddle of the Universe”) that the ether must be like some extremely attenuated jelly, and that a sphere of it the size of the earth would probably weigh about 250 pounds! Such crude conceptions have long since been given up. It is far more subtle than this. Is it analogous to the finest gas? Some have thought so; and yet Sir Oliver Lodge, one of the greatest authorities upon the ether, has contended that it is more dense and solid than platinum or gold, and that matter represents mere “bubbles” within this dense medium, capable of moving freely through it. In support of this view, he has cited (in his “Ether of Space”) the enormous gravitational pull of the earth upon the moon, _e. g._, or of the sun upon the earth. The mass of the earth is approximately 6,000 trillion tons; that of the moon one-eightieth of this. From these data, the gravitational pull of the earth upon the moon can be calculated; and, regarding this, Sir Oliver says:

“A pillar of steel which could transmit this force, provided it could sustain a tension of 40 tons to the square inch, would have a diameter of about 400 miles.... If this force were to be transmitted by a forest of weightless pillars, each a square foot in cross section, with a tension of 30 tons to the square inch throughout, there would have to be 5 million million of them.”

Calculating the gravitational pull of the sun on the earth, in a similar manner, it was calculated that the strain in this case would have to be borne by “a million million round rods or pillars each thirty feet in diameter.”

It may readily be seen, then, from these figures, that something enormously dense, apparently, must exist in order to bear this strain, and this must be the ether. And yet no physical experiments have proved to us the existence of the ether; we only infer its presence, and say that it _must_ exist, in order to account for certain phenomena observed in physics. It was, I think, Lord Kelvin who remarked that no man could believe in the ether without at the same time believing it to possess opposite and contradictory properties! Indeed, it would seem so!

CHEMISTRY AND META-PHYSICS

Such speculations as these lead us far afield, into the realm of mathematics, metaphysics and ultimate realities. Even the most material of all the sciences--chemistry--leads thither when pushed to its final analysis. The visible, sensible universe vanishes, and is replaced by the invisible, the super-sensible. Yet science has been our guide throughout. William James once remarked that metaphysics is merely “persistently clear thinking.” It endeavors to find the ultimate causes of things, the _noumena_ behind phenomena, the reality behind appearances. The physical world in which we live is a world of phenomena only; real in a sense, and for all practical purposes, and yet the greatest of all unrealities in another sense. It is a mere world of appearances; a phantasmagoria of fleeting shapes and shadows. We feel that reality must exist somehow, somewhere; yet we can never find it. We can no more find it by chemical analysis than we can discover the mind and soul of man by dissecting the brains of corpses,--or even by vivisection! Something always escapes us--the Soul of Things, the Ultimate Reality, the Great Unknown.

Such thoughts and speculations as these, however, need not occupy the mind of the practical chemist. For him, atoms exist, so do elements, so does “matter.” For practical, daily life, we certainly have to live _as if_ matter existed, and the chemist has to proceed with his work upon the assumption that matter actually does exist--it is “real.” Certain it is that the practical furtherance and application of this science can come about in no other way. Chemistry has revolutionized our lives; it has penetrated all fields of commerce and industry, and its practical application has rendered possible and pleasant the lives of countless thousands of persons now living upon our planet. We owe more to chemistry than we can ever repay--or rather to those brilliant and unselfish men who have built up the modern science of chemistry. It is my hope that the present little book may in some degree have helped to emphasize this fact.

Transcriber’s Notes

Punctuation, hyphenation, and spelling were made consistent when a predominant preference was found in the original book; otherwise they were not changed.

Simple typographical errors were corrected; unbalanced quotation marks were remedied when the change was obvious, and otherwise left unbalanced.

This book uses both “reactions” and “reäctions”.

Page 17: “Cobalt” was printed as “Cobolt”; changed here.

Page 23: The “constitutional” formula in the original book was printed with the two “B”s stacked, one above the other, and in a smaller font that could fit both of them on one line of normal-sized text.

Page 49: “allotrophic” was printed that way; probably should be “allotropic”.