'Tis evident, that as common Air when reduc'd to half Its wonted extent, obtained near about twice as forcible a Spring as it had before; so this thus- comprest Air being further thrust into half this narrow room, obtained thereby a Spring about as strong again as that It last had, and consequently four times as strong as that of the common Air. And there is no cause to doubt, that If we had been here furnisht with a greater quantity of Quicksilver and a very long Tube, we might by a further compression of the included Air have made It counter-balance 'the pressure' of a far taller and heavier Cylinder of Mercury. For no man perhaps yet knows how near to an infinite compression the Air may be capable of, If the compressing force be competently increast.

On the future of Chemistry:
Chemistry is not the preservation hall of old jazz that it sometimes looks like. We cannot know what may happen tomorrow. Someone may oxidize mercury (II), francium (I), or radium (II). A mineral in Nova Scotia may contain an unsaturated quark per 1020 nucleons. (This is still 6000 per gram.) We may pick up an extraterrestrial edition of Chemical Abstracts. The universe may be a 4-dimensional soap bubble in an 11-dimensional space as some supersymmetry theorists argued in May of 1983. Who knows?

A barbarous practice, the inconsistency, folly, and injury of which no words can sufficiently describe.
Condemning the use of mercurial medicines.

A night with Venus, a lifetime with Mercury.
[For centuries mercury was used as a treatment for syphilis.]

Albertus [Magnus] ... debased the doctrine of Aristotle with the itch of the chemists flowing with the bloody flux of quicksilver and the stench of sulphur.

But what exceeds all wonders, I have discovered four new planets and observed their proper and particular motions, different among themselves and from the motions of all the other stars; and these new planets move about another very large star [Jupiter] like Venus and Mercury, and perchance the other known planets, move about the Sun. As soon as this tract, which I shall send to all the philosophers and mathematicians as an announcement, is finished, I shall send a copy to the Most Serene Grand Duke, together with an excellent spyglass, so that he can verify all these truths.

Consider the eighth category, which deals with stones. Wilkins divides them into the following classifications: ordinary (flint, gravel, slate); intermediate (marble, amber, coral); precious (pearl, opal); transparent (amethyst, sapphire); and insoluble (coal, clay, and arsenic). The ninth category is almost as alarming as the eighth. It reveals that metals can be imperfect (vermilion, quicksilver); artificial (bronze, brass); recremental (filings, rust); and natural (gold, tin, copper). The whale appears in the sixteenth category: it is a viviparous, oblong fish. These ambiguities, redundances, and deficiencies recall those attributed by Dr. Franz Kuhn to a certain Chinese encyclopedia entitled Celestial Emporium of Benevolent Knowledge. On those remote pages it is written that animals are divided into (a) those that belong to the Emperor, (b) embalmed ones, (c) those that are trained, (d) suckling pigs, (e) mermaids, (f) fabulous ones, (g) stray dogs, (h) those that are included in this classification, (i) those that tremble as if they were mad, (j) innumerable ones, (k) those drawn with a very fine camel's hair brush, (l) others, (m) those that have just broken a flower vase, (n) those that resemble flies from a distance.

He, who for an ordinary cause, resigns the fate of his patient to mercury, is a vile enemy to the sick; and, if he is tolerably popular, will, in one successful season, have paved the way for the business of life, for he has enough to do, ever afterward, to stop the mercurial breach of the constitutions of his dilapidated patients. He has thrown himself in fearful proximity to death, and has now to fight him at arm's length as long as the patient maintains a miserable existence.

I had rather be Mercury, the smallest among seven [planets], revolving round the sun, than the first among five [moons] revolving round Saturn.

I therefore concluded, and decided unhesitatingly, that there are three stars in the heavens moving about Jupiter, as Venus and Mercury about the Sun; which at length was established as clear as daylight by numerous other observations.
Referring to his pioneering telescope observations.

I wol yow telle, as was me taught also,
The foure spirites and the bodies sevene,
By ordre, as ofte I herde my lord hem nevene.
The firste spirit quiksilver called is,
The second orpiment, the thridde, ywis,
Sal armoniak, and the firthe brimstoon.
The bodies sevene eek, lo! hem heer anoon:
Sol gold is, and Luna silver we threpe,
Mars yron, Mercurie quiksilver we clepe,
Saturnus leed, and Jupiter is tin,
And Venus coper, by my fader kin!

If you could see what I almost daily see in my practice … persons … in the very last stages of wretched existence, emaciated to a skeleton, with both tables of the skull almost completely perforated in many places, half the nose gone, with rotten jaws, ulerated throats, breaths most pestiferous more intolerable than poisonous upas, limbs racked with the pains of the Inquisition, minds as imbecile as the puling babe, a grievous burden to themselves and a disgusting spectacle to others, you would exclaim as I have often done, 'O! the lamentable want of science that dictates the abuse (use) of that noxious drug calomel!'
[Calomel is the mercury compound, Hg₂Cl₂.]

In 1810, the Triumph man-of-war and Phipps schooner received on board several tons of quicksilver, saved from the wreck of a vessel near Cadiz. In consequence of the rolling of the bags the mercury escaped, and the whole of the crews became more or less affected. In the space of three weeks, two hundred men were salivated, two died, and all the animals—cats,dogs,sheep,fowls,a canary bird, nay, even the rats, mice and cockroaches'were destroyed.
[The leather bags of mercury had been salvaged and stored without the original wooden cases. Some were stowed in sleeping quarters, and the in same hold as spirit rations.]

It seeming impossible in any other manner to properly restrict the use of this powerful agent [calomel, a mercury compound, mercurous chloride], it is directed that it be struck from the supply table, and that no further requisitions for this medicine be approved by Medical Directors. ... modern pathology has proved the impropriety of the use of mercury in very many of those diseases in which it was formerly unfailingly administered. ... No doubt can exist that more harm has resulted from the misuse [of this agent], in the treatment of disease, than benefit from their proper administration.
W.A. Hammond, Surgeon General, Washington D.C., 4 May 1863

Learning is like mercury, one of the most powerful and excellent things in the world in skillful hands; in unskillful, the most mischievous.

The experiment left no doubt that, as far as accuracy of measurement went, the resistance disappeared. At the same time, however, something unexpected occurred. The disappearance did not take place gradually but abruptly. From 1/500 the resistance at 4.2K, it could be established that the resistance had become less than a thousand-millionth part of that at normal temperature. Thus the mercury at 4.2K has entered a new state, which, owing to its particular electrical properties, can be called the state of superconductivity.

We have made many glass vessels... with tubes two cubits long. These were filled with mercury, the open end was closed with the finger, and the tubes were then inverted in a vessel where there was mercury. We saw that an empty space was formed and that nothing happened in the vessel where this space was formed ... I claim that the force which keeps the mercury from falling is external and that the force comes from outside the tube. On the surface of the mercury which is in the bowl rests the weight of a column of fifty miles of air. Is it a surprise that into the vessel, in which the mercury has no inclination and no repugnance, not even the slightest, to being there, it should enter and should rise in a column high enough to make equilibrium with the weight of the external air which forces it up?

When it is considered that this light, when obtained with mercury gas, has an efficiency at least eight times as great as that obtained by an ordinary incandescent lamp, it will be appreciated that it has its use in places where lack of red is not important, for the economy of operation will much more than compensate for the somewhat unnatural color given to illuminated objects.

Yet in this my stars were not Mercury as morning star in the angle of the seventh house, in quartile with Mars, but they were Copernicus, they were Tycho Brahe, without whose books of observations everything which has now been brought by me into the brightest daylight would lie buried in darkness.

[Mercurial medicines] affect the human constitution in a peculiar manner, taking, so to speak, an iron grasp of all its systems, and penetrating even to the bones, by which they not only change the healthy action of its vessels, and general structure, but greatly impair and destroy its energies; so that their abuse is rarely overcome. When the tone of the stomach, intestines, or nervous system generally, has been once injured by this mineral ... it could seldom be restored.