Ole Christian Roemer, a Danish astronomer having studyied Jupiter’s moons from 1671 to 1677, observes that light moves at a finite speed.

The Polish-Ottoman War of 1672-16 has showed the increasing weakness and disorder of the Commonwealth, which by the second half of the seventeenth century had started the gradual decline that is to culminate a century later in the partitions of Poland.

The unruly Sejm, paralyzed by liberum veto and foreign bribery, is dominated by politicians who think in short term gains only and constantly refuse the funds to raise an army, as it appears that most of the Commonwealth will not be ravaged by the Ottoman armies.

Even after the unfavorable Buczacz treaty, which had persuaded the Sejm to raise the taxes, once initial successes were achieved, the majority of the Sejm again couldn't be convinced to keep up the pressure on the enemy; soldiers are left unpaid and desertions on a mass scale negatively affect the Polish cause.

This apparent inability to defend itself, also seen in the other recent and future conflicts involving the Commonwealth, increasingly invites foreign forces to prey on the country.

The sect of Sabbatai Zevi survives largely thanks to the activity of Nathan of Gaza, a tireless propagandist for the “Messiah”, who had been forcibly converted to Islam in 1666 and ended his life in Montenegrin exile ten years later.

Nathan justifies the actions of Sabbatai, which were contrary to the Law, and his final apostasy by theories that are based on the Lurian theory of “repair”, which is to be understood as the descent of the just into the abyss of the ”shell” in order to liberate from it the captive particles of divine light.

Sabbateanism continues to flourish: the sect attempts to reconcile Sabbetai's grandiose claims of spiritual authority with his subsequent seeming betrayal of the Jewish faith.

Faithful Sabbateans interpret Sabbetai's apostasy as a step toward ultimate fulfillment of his messiahship and attempt to follow their leader's example.

They argue that such outward acts are irrelevant as long as one remains inwardly a Jew.

Those who embrace the theory of “sacred sin” believe that the Torah can be fulfilled only by amoral acts representing its seeming annulment.

Others feel they can remain faithful Sabbateans without having to apostatize.

The first recipe in French for flavored ices appears in 1674, in Nicholas Lemery’s Recueil de curiositéz rares et nouvelles de plus admirables effets de la nature.

Ice cream has by 1677 become a popular dessert in Paris, a city that is at this time home to more than five hundred thousand people.

The chapel of Emmanuel College, a constituent college of the University of Cambridge, is designed by Christopher Wren in 1677 replacing the original chapel, which becomes the library.

The Province of New York orders the Susquehannock to be expelled from the Delaware Valley in 1677.

Governor Andros had told the Susquehannock they would be welcome in New York and that he would protect them from Maryland and Virginia.

The Mohawk Nation had invited them to move to New York as guests of the Iroquois.

Some have moved back to their homeland on the Susquehanna River, some have fled to the Iroquois for shelter, and others have moved to the upper Delaware River under the protection of New York.

After adopting the majority of the Susquehannock tribe, the Iroquois acquires a right to most of the Susquehanna River, but they never claim below the falls.

Two hundred settlers from the towns of Chorleywood and Rickmansworth in Hertfordshire and other towns in nearby Buckinghamshire arrive also in 1677 and establish the town of Burlington.

George Fox himself had made a journey to America to verify the potential of further expansion of the early Quaker settlements.

The English relief force arrives in January 1677. 

Governor Berkeley is relieved of the governorship after an investigative committee returns its report to King Charles II, and returns to England.

Phèdre (originally Phèdre et Hippolyte), a dramatic tragedy in five acts written in alexandrine verse by Jean Racine, is first performed on January 1, 1677.

Racine has chosen once more a subject from Greek mythology, already treated by Greek and Roman tragic poets, notably by Euripides in Hippolytus and Seneca in Phaedra.

In the absence of her royal husband Thésée, Phèdre ends by declaring her love to Hippolyte, Thésée's son from a previous marriage.

As a result of an intrigue by the Duchess of Bouillon and other friends of the aging Pierre Corneille, the play is not a success at its première at the Hôtel de Bourgogne, home of the royal troupe of actors in Paris.

Indeed a rival group stages a play by the now forgotten playwright Nicolas Pradon on an almost identical theme.

After Phèdre, Racine is to cease writing plays on secular themes and for the next dozen years devote himself to the service of religion and the king.

Certain lines from the play, such as "la fille de Minos et de Pasiphaé", are to become classics in the French language; but despite the celebrated musicality of the alexandrine, Racine never wrote poetry just for the sake of beauty of sound.

Despite its author's silence from 1677 to 1689, as time progresses Phèdre will become one of the most famous of his plays.

It is today one of the most frequently staged tragedies from the seventeenth century.

The Affair of the Poisons proper opens in February 1677 after the arrest of Magdelaine de La Grange on charges of forgery and murder.

She appeals to François-Michel le Tellier, Marquis de Louvois, claiming that she has information about other crimes of high importance.

Louvois reports to the King, who tells Gabriel Nicolas de la Reynie, who, among other things, is the chief of the Paris police, to root out the poisoners.

La Reynie seeks to calm the King.

The subsequent investigation of potential poisoners leads to accusations of witchcraft, murder and more.

Authorities rounds up a number of fortune tellers and alchemists that are suspected of selling not only divinations, séances and aphrodisiacs, but also "inheritance powders" (aka: poison).

Some of them confess under torture and give the authorities lists of their clients, who had allegedly bought poison to either get rid of their husbands or rivals in the court.