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CHAPTER VIII.

DR. BRYAN HIGGINS AND WILLIAM HIGGINS.

DR. BRYAN Higgins was the earliest chemist who seems to have dealt with the elements of matter, in a chemical, as well as physical sense, with an attempt to obtain information as to the primary elements and their atomic constitution, although he gives no certain results. I find at the laboratory of Owens College, among the books forming part of the library of the late Dr. William Henry, a little pamphlet, proposing a course of lectures, to be commenced on the 13th November, 1775.

The proposals are said to have been formerly published ; it is not said how long before. I shall give considerable extracts.

Page 1. “ Doctor Higgins, of Greek-street, Soho, encouraged by the literary noblemen, and gentlemen who have subscribed to his courses of philosophic and practical chemistry, addresses the following proposals to the patrons of natural philosophy and useful arts.

66 That fifty philosophic and literary gentlemen do concur in promoting experimental inquiries into the elements of matter and laws of nature, and such other subjects as are most important in natural philosophy, chemistry, and arts.

Page 3. “ That in these discourses he shall introduce the natural phenomena, the illustrative observations and experiments of philosophers, chemists, and artists; and particularly his notions and experiments concerning the primary elements and the properties of matter.

Page 9. “ Introductory discourse on matter in general, called gross matter; on the varieties and distinctions of gross matter; on the primary elements of matter.

“ Observations on the experiments and philosophy exhibited in the foregoing course of chemistry, and other experiments which demonstrate the existence of seven primary distinct elements of matter, viz.; Earth,

Air,
Water,

Phlogiston,
Alkali,

Light. Acid, “ Experiments, observations, and arguments, persuading that each primary element consists of atoms homogeneal; that these atoms are impenetrable, immutable in figure, inconvertible, and that, in the ordinary course of nature, they are not annihilated, nor newly created.

“ Observations and experiments, persuading that the atoms of each element are globular, or nearly so, and that the spiral, spicular and other figures ascribed to these atoms, are fictions unnecessary, and are inconsistent with the uniformity and simplicity of nature, and repugnant to experience.

“ Experiments and observations showing that the possible and known unions of the foregoing elements, and that the possible and known proportions in which the unions of the foregoing elements may take place, are more numerous than the bodies distinguished by philosophers and naturalists; persuading that all known bodies are really composed of one or more of the foregoing elements; and that all bodies must be admitted to consist of these only until other elementary matter is found necessary for the explication of the natural phenomena, and is demonstrated to exist.

“ A classical arrangement on the table of bodies composed of two or three primary elements, which bodies, in various chemical processes, not being decomposed, we call chemical elements, or the elements of the chemists.

“A like classical arrangement of bodies composed of two chemical elements.

“A like classical arrangement of bodies and natural substances composed of many chemical elements.

OPINION, “1. That the homogeneal atoms of five elements repel reciprocally.

2. That the homogeneal atoms of two elements attract reciprocally.

“3. That the dissimilar atoms of five elements attract reciprocally.

“4. That the dissimilar atoms of two elements repel reciprocally

" That the attraction subsisting between elementary atoms is more forcible in one direction or axis of each atom than in any other direction, and that there is a polarity in all matter whatever.

66. That there is but one species of attraction operating with great force between the similar or dissimilar atoms of certain elements, and with less force between those of other elements, in gradations; but in all affected by distance and polarity

667. That the attraction of bodies enumerated as distinct properties of matter or laws of nature, are nothing more than the sums of the attraction of their elementary atoms, or these forces concentrated in a certain degree by the pressure of repellent atoms, or these forces exerted to the greatest advantage in bodies whose primary elementary attractions are strongest, and whose primary elementary atoms are also arranged in polar order.

“8. That specific gravity is not as the quantity of matter in a given space, but as the quality of the matter, or the sum of its elementary attractions; consequently, that light bodies are not necessarily more porous than the heaviest.”

Page 14. “Observations and experiments, showing the grounds on which we ought for a while to admit the following distinctions of earths, viz:

Z

“ Seven earths, capable of forming ductile metals.
“ Seven earths, capable of forming metals not ductile.
“Seven earths, incapable of forming metal.

Question 1. Is there but one earthy element, which, in various modes of aggregation, or in indissoluble combination with other elementary matter, forms twenty-one earthy bodies ? or, Question 2, Are there three times seven, or seven times seven earthy elements ?

Page 15. “Experimental and geometrical estimation of the force of this attraction in fortuitous arrangement of the atoms, and of the force of this attraction in the polar arrangement of the atoms.

On attraction he says, page 23, “ That no element doth saturate, nor can saturate, the like element; that no element, whose atoms attract each other, can saturate any other element whose atoms attract each other; that a repellent element doth saturate non-repellent elements, and vice versa ; that repellent elements do saturate reciprocally; and that attraction and repulsion, operating adversely, are the cause of saturation ; and saturation is not a distinct or primary law of nature, but an effect.”

We find here no ideas given of definite compounds, except so far as the ordinary idea of saturation is concerned. Had Dr. Higgins any theory resembling the present atomic theory, he would certainly not have expressed himself so darkly on the subject of saturation.

We even find that he is not quite freed from the prima materia, although he restricts it to the matter of certain classes, such as the matter of earth forming many earths, the acid matter forming many acids. He is, therefore, to be viewed as one bordering on the transmutation theory, not freed from mystic ideas, but grappling with the subject so energetically, that in some directions he almost sees his way into another region of theory.

I shall quote the most important sentences in the “ Experi

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ments and observations”* of Dr. Higgins. In distilling acetate of lead, he found a certain amount of what he calls acid matter in the fixable air, which he considers, as before mentioned, to be a peculiar principle. It combines with the empyreal air (oxygen) of the litharge. Not accounting for the whole amount by the measurements he made, he inferred 6 that when the acid matter of acetous acid is employed in excessive quantity to form fixable air with the empyreal air of litharge, the fixable air may consist of a little more than one part of the acid matter, combined with two of the empyreal air. By a more accurate estimate of the fixable air taken at 85 grains, it is most probable that the proportions would be found to be accurately two to one, provided fixable air, like other acids, may not subsist with various proportions of the empyreal air." +

He mentions the definite proportion, two to one, because he obtains the figures approximatively so, but he not only fails to elevate it into a principle, but speaks of various proportions as probable in the case in hand, anıl as usual in other cases. This seems equal to saying distinctly that he recognised no such principle. But does the term “various proportions allude to fixed numbers, such as two or three? There is no reason to suppose this, he uses the word in the ordinary sense it was then used, no other sense had been given to it, and any other sense in this place is impossible.

When firing with oxygen the inflammable gases from acetate of lime, he says, in reference to some experiments unnecessary to be detailed, “by other experiments and the same kind of estimation, the empyreal air appeared to constitute more than two-thirds of the fixable air, and in some it seemed to be accurately two-thirds; but after all I continued

* Experiments and observations relating to acetous acid, fixable air, dense inflammable air, oils and fuel. The matter of fire and light, metallic reduction, combustion, fermentation, putrefaction, respiration, and other subjects of chemical philosophy. By Bryan Higgins, M.D. London, 1786,

† Page 232.

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