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comfort, not a food, but what he believes to be a solace.

"Sublime Tobacco! which from East to West

Cheers the tar's labour or the Turkman's rest."

In the United States alone, in the year 1885, there were 752,520 acres of land devoted to the production of tobacco, the amount in pounds grown being 562,736,000, and the value of which was estimated as $43,265,598. These amounts have been somewhat less in years since then, but the appetite continues, and any deficiency in the supply is made up by enormous importation. Thus, in 1896, there were imported into the United States, 32,924,966 pounds of tobacco, of various kinds, valued at $16,503,130. There are no reliable statistics showing that, man for man, the people of that country are greater lovers of the weed than the people of other countries, but the annual value of tobacco raised and imported by them being thus about $60,000,000, it indicates the strength of the habit and the interest in the nurture of the plant throughout the world. Neither the "Counterblaste to Tobacco" of King James I., and the condemnations of kings, popes, priests and sultans, that followed its early introduction into Europe, served to choke the weed in its infancy or check its after growth. Now it is attended from the day of its planting until it reaches the lips of the consumer by contrivances of consummate skill to fit it for its destined purpose. sides the ploughs, the cultivators and the weeders of especial forms used to cultivate the plant, there are, after the grown plant is cut in the field, houses of various designs for drying it, machines for rolling the leaves out smoothly in sheets; machines for re

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moving the stems from the leaves and for crushing the stem; machines for pressing it into shape, and for pressing it, whether solid or in granular form, into boxes, tubs and bags; machines for granulating it and for grinding it into snuff; machines for twisting it into cords; machines for flavouring the leaf with saccharine and other matters; machines for making cigars, and machines of a great variety and of the most ingenious construction for making cigarettes and putting them in packages.

Samples of pipes made by different ages and by different peoples would form a collection of wonderful art and ingenuity, second only to an exhibition of the means and methods of making them.

CHAPTER VI.

CHEMISTRY.

CHEMISTRY, having for its field the properties and changes of matter, has excited more or less attention ever since men had the power to observe, to think, and to experiment.

Some knowledge of chemistry must have existed among the ancients to have enabled the Egyptians to smelt ores and work metals, to dye their cloths, to make glass, and to preserve their dead from decomposition; so, too, to this extent among the Phonicians, the Israelites, the Greeks and the Romans; and perhaps to a greater extent among the Chinese, who added powder to the above named and other chemical products. Aristotle speculated, and the alchemists of the middle ages busied themselves in magic and guess-work. It reached the dignity of a science in the seventeenth and eighteenth centuries, by the labours of such men, in the former century, as Libavius, Van Helmont, Glauber, Tachenius, Boyle, Lémery and Becher; Stahl, Boerhaave and Hamberg in both; and of Black, Cavendish, Lavoisier, Priestley and others in the eighteenth.

But so great have been the discoveries and inventions in this science during the nineteenth century that any chemist of any previous age, if permitted to look forward upon them, would have felt

"Like some watcher of the skies

When a new planet swims into his ken.”

Indeed, the chemistry of this century is a new world, of which all the previous discoveries in that line were but floating nebulæ.

So vast and astonishingly fast has been the growth and development of this science that before the century was two-thirds through its course Watts published his Dictionary of Chemistry in five volumes, averaging a thousand closely printed pages, followed soon by a thousand-page supplement; and it would have required such a volume every year since to adequately report the progress of the science. Nomenclatures, formulas, apparatuses and processes have all changed. It was deemed necessary to pub lish works on The New Chemistry, and Professor J. P. Cooke is the author of an admirable volume under that title.

We can, therefore, in this chapter only step from one to another of some of the peaks that rise above the vast surrounding country, and note some of the lesser objects as they appear in the vales below.

The leading discoveries of the century which have done so much to aid Chemistry in its giant strides are the atomic and molecular theories, the mechanics of light, heat, and electricity, the correlation and conservation of forces, their invariable quantity, and their indestructibility, spectrum analysis and the laws of chemical changes.

John Dalton, that humble child of English northcountry Quaker stock, self-taught and a teacher all his life, in 1803 gave to the world his atomic theory of chemistry, whereby the existence of matter in ultimate atoms was removed from the region of the speculation of certain ancient philosophers, and established on a sure foundation.

The question asked and answered by Dalton was, what is the relative weight of the atoms composing the elementary bodies?

He discovered that one chemical element or compound can combine with another chemical element, to form a new compound, in two different proportions by weight, which stand to each other in the simple ratio of one to two; and at the same time he published a table of the Relative weight of the ultimate particles of Gaseous and other Bodies. Although the details of this table have since been changed, the principles of his discovery remain unchanged. Says Professor Roscoe:

"Chemistry could hardly be said to exist as a science before the establishment of the laws of combination in multiple proportions, and the subsequent progress of chemical science materially depended upon the determination of these combined proportions or atomic weights of the elements first set up by Dalton. So that among the founders of our science, next to the name of the great French Philosopher, Lavoisier, will stand in future ages the name of John Dalton, of Manchester."

Less conspicuous but still eminently useful were his discoveries and labours in other directions, in the expansion of gases, evaporation, steam, etc.

Wollaston and Gay-Lussac, both great chemists, applied Dalton's discovery to wide and most important fields in the chemical arts.

Also contemporaneous with Dalton was the great German chemist, Berzelius, who confirmed and extended the discoveries of Dalton. More than this, it has been said of Berzelius:

"In him were united all the different impulses which have advanced the science since the beginning

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