December 2001
Vol. 31, No. 12, pp 62–63.
Learning from the Past

Table of Contents

Weldon Vlasak

The miraculous engine

One of the most important attributes of great scientists of the past was their ability to take an objective viewpoint and see the overall picture of a problem. They were also able to simplify complex issues in order to solve extremely difficult problems. Max Planck, for instance, used only five basic mathematical equations to derive some of the established laws of chemistry from seven known and measured chemical reactions and thus establish the validity of his approach. Two of these equations formed the basis of his quantum theory, for which he eventually received the Nobel Prize.

There are other such outstanding examples of investigative methodology of the past. This article contains excerpts from the recorded lectures of another famous master scientist (1), whose name you may be able to guess. The first excerpt is from a description of the properties of what is currently referred to as a common “greenhouse gas”.

Let me take that piece of sugar, which will serve my purpose. It is a compound of carbon, hydrogen, and oxygen, similar to a candle, . . . containing the same elements, though not in the same proportion, the [mass] proportions [for sugar] being as shown in [this] table:

Carbon
72
Hydrogen
11
} 99
Oxygen
88

This is, indeed, a very curious thing, which you can well remember, for the oxygen and hydrogen are in exactly the proportions which form water, so that sugar may be said to be compounded of 72 parts of carbon and 99 parts of water; and it is the carbon in the sugar that combines with the oxygen carried in by the air in the process of respiration, so making us like candles; producing these actions, warmth and far more wonderful results besides, for the sustenance of the system, by a most beautiful and simple process. To make this still more striking, I will take a little sugar; or to hasten the experiment, I will use some sirup [sic], which contains about three fourths of sugar and a little water. If I put a little oil of vitriol in it, it takes away the water, and leaves the carbon in a black mass. [The lecturer mixed the two together.] You see how the carbon is coming out, and before long we shall have a solid mass of charcoal, all of which has come out of sugar. Sugar, as you know, is food, and here we have absolutely a solid lump of carbon where you would not have expected it. And if I make arrangements so as to oxidize the carbon of sugar, we shall have a much more striking result. Here is sugar, and I have here an oxidizer—a quicker one than the atmosphere; and so we shall oxidize this fuel by a process different from respiration in its form, though not different in its kind. It is the combustion of the carbon by the contact of oxygen which the body has supplied to it. If I set this into action at once, you will see combustion produced. Just what occurs in my lungs—taking in oxygen from another source, namely, the atmosphere, takes place here by a more rapid process.

The lecturer devised a simple and neat demonstration of the decomposition of sugar into water and carbon, followed by the generation of carbon dioxide (a greenhouse gas) from the oxidation of sugar.

Pollution of the environment
The lecturer goes on to describe certain generators of greenhouse gases:

    You will be astonished when I tell you what this curious play of carbon amounts to. A candle will burn 5, 6, or 7 hours. What, then, must be the daily amount of carbon going up into the air in the way of carbonic acid [CO2]! What a quantity of carbon must go from each of us in respiration! What a wonderful change of carbon must take place under these circumstances of combustion or respiration! A man in 24 hours converts as much as 7 ounces of carbon into carbonic acid; a milk cow will convert 70 ounces, and a horse 79 ounces, solely by the act of respiration. That is, the horse in 24 hours burns 79 ounces of charcoal, or carbon, in his organs of respiration to supply his natural warmth in that time. All the warm-blooded animals get their warmth in this way, by the conversion of carbon, not in a free state, but in a state of combination. And what an extraordinary notion this gives us of the alterations going on in our atmosphere. As much as 5,000,000 pounds, or 548 tons [sic], of carbonic acid is formed by respiration in London alone in 24 hours. And where does all this go? Up into the air.

We don’t see much mention of this source of greenhouse gas in the media today, though there have been some articles written about gases emitted by ruminant livestock.

Pollution control
The lecturer proceeds to show how the carbon dioxide produced by respiration is disposed of.

    If the carbon had been like the lead which I showed you, or the iron which, in burning, produces a solid substance, what would happen? Combustion could not go on. As charcoal burns it becomes a vapor and passes off into the atmosphere, which is the great vehicle, the great carrier for conveying it away to other places. Then what becomes of it? Wonderful is it to find that the change produced by respiration, which seems so injurious to us (for we cannot breathe air twice over), is the very life and support of plants and vegetables that grow upon the surface of the earth. It is the same also under the surface, in the great bodies of water; for fishes and other animals respire upon the same principle, though not exactly by contact with the open air.

    Such fish as I have here [pointing to a globe of goldfish] respire by the oxygen which is dissolved from the air by the water, and form carbonic acid, and they all move about to produce the one great work of making the animal and vegetable kingdoms subservient to each other. And all the plants growing upon the surface of the earth, like that which I have brought here to serve as an illustration, absorb carbon; these leaves are taking up their carbon from the atmosphere to which we have given it in the form of carbonic acid, and they are growing and prospering. Give them a pure air like ours, and they could not live in it; give them carbon with other matters, and they live and rejoice.

The plants rejoice at getting the greenhouse gas! Nothing like a happy plant.

    This piece of wood gets all its carbon, as the trees and plants get theirs, from the atmosphere, which, as we have seen, carries away what is bad for us and at the same time good for them—what is disease to the one being health to the other. So are we made dependent not merely upon our fellow-creatures, but upon our fellow-existers, all Nature being tied together by the laws that make one part conduce to the good of another.

Fuel with a shelf life of millennia
The lecturer goes on to illustrate the different stabilities of fuels:

    There is another little point which I must mention before we draw to a close—a point which concerns the whole of these operations, and most curious and beautiful it is to see it clustering upon and associated with the bodies that concern us—oxygen, hydrogen, and carbon, in different states of their existence. I showed you just now some powdered lead, which I set burning; and you saw that the moment the fuel was brought to the air it acted, even before it got out of the bottle—the moment the air crept in it acted. Now there is a case of chemical affinity by which all our operations proceed. When we breathe, the same operation is going on within us. When we burn a candle, the attraction of the different parts one to the other is going on. Here it is going on in this case of the lead, and it is a beautiful instance of chemical affinity. If the products of combustion rose off from the surface, the lead would take fire, and go on burning to the end; but you remember that we have this difference between charcoal and lead—that, while the lead can start into action at once if there be access of air to it, the carbon will remain days, weeks, months, or years. The manuscripts of Herculaneum were written with carbonaceous ink, and there they have been for 1800 years or more, not having been at all changed by the atmosphere, though coming in contact with it under various circumstances. Now, what is the circumstance which makes the lead and carbon differ in this respect? It is a striking thing to see that the matter which is appointed to serve the purpose of fuel waits in its action; it does not start off burning, like the lead and many other things that I could show you, but which I have not encumbered the table with; but it waits for action. This waiting is a curious and wonderful thing.

The lead described in the above reaction is “lead pyrophorous”, which is made by “heating dry tartrate of lead in a closed tube” until the reaction is complete and the vapors are drawn out. This material will burn in open air at room temperature. Carbon is clearly one of the most stable fuels found on Earth.

The miraculous engine
The lecturer discusses the processes by which coal gas, gun-cotton, and gunpowder react under different conditions and different temperatures. He goes on to describe a remarkable engine that burns the carbon over a wide range of temperature.

    How beautifully that shows you the difference in the degree in which bodies act in this way! In the one case, the substance will wait any time until the associated bodies are made active by heat; but in the other, as in the process of respiration, it waits no time. In the lungs, as soon as the air enters, it unites with the carbon; even in the lowest temperature which the body can bear short of being frozen, the action begins at once, producing the carbonic acid of respiration; and so all things go on fitly and properly. Thus you see the analogy between respiration and combustion is rendered still more beautiful and striking.

The human body is truly a unique and miraculous engine. This scientist had been conducting lectures to “juveniles” in an effort to expound the virtues of science, and these excerpts were taken from the sixth lecture on a subject entitled “Chemical History of a Candle”. He closes these lectures with a bit of subtle humor:

    Indeed, all I can say to you at the end of these lectures (for we must come to an end at one time or other) is to express a wish that you may, in your generation, be fit to compare to a candle; that you may, like it, shine as lights to those about you; that, in all your actions, you may justify the beauty of the taper by making your deeds honorable and effectual in the discharge of your duty to your fellow man.

This scientist could well be compared to a candle in accordance with the above description. He was born near London in 1791, the son of a blacksmith. After 8 years of apprenticeship as a bookbinder and stationer, he was employed as the laboratory assistant to Sir Humphrey Davy, who made numerous contributions to the field of chemistry, at the Royal Institution. He had a special talent for and interest in science and rose rapidly through the ranks, conducting exhaustive investigations of the basic characteristics of matter and making numerous discoveries. His contributions to the knowledge of chemistry and physics include the discovery of the Law of Electrolysis, magneto-electric induction, diamagnetism, and the concept of electrical capacitance. The unit of capacitance, the farad, is named after him, as is the charge of 1 mole of electrons, the Faraday constant. After making some of these important discoveries, he was offered the presidencies of the Royal Society and the Royal Institution but declined the offers.

This “greatest experimental philosopher” (as described by his successor, John Tyndall) and extraordinary investigator, Michael Faraday, died on August 25, 1867.

Reference

  1. Eliot, C. W. Scientific Papers; The Harvard Classics; P. F. Collier & Son: New York, 1910; Vol. 30, Lecture VI, pp 163–178.


Weldon Vlasak is an engineering consultant at Adaptive Enterprises Inc. (9099 W. State Hwy. 41, Clatonia, NE 68328; 402-989-6225; adaptent@alltel.net).

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