Gravitate to the planting of Newton's apple tree on Feb. 22

  • Preparing for Newton Day
    Preparing for Newton Day
    Faculty involved in Newton Day events check out Swem Library's Copy of Newton's "Principia" … and some apples. Highlight of the Feb. 22 event is planting of a descendant of Isaac Newton’s original tree. From left are Liz Wiley, theatre; Marc Sher, physics; Martha Case, biology; and Josh Erlich, physics.
    Photo by Joseph McClain

The hyper-rational world of science has always made a bit of room to accommodate legend and William & Mary will soon be home to a living piece of one of the most well-known scientific legends: a descendant of Isaac Newton’s apple tree.

A ceremonial planting will be held at 2 p.m. Feb. 22 outside Small Hall, home of William & Mary’s Department of Physics. The planting ceremony, to be moved inside Small Hall in case of inclement weather, is the highlight of Newton Day festivities. Other activities include Newtonfest, an Isaac-themed version of the physics department’s popular open houses aimed at school-age children. Dava Sobel, author of books such as Longitude and Galileo’s Daughter, will participate, as will Newton expert Mordecai Finegold. The university’s Department of Theatre will present a play by Sobel, as well.

All events are open to the public. A complete schedule is available here.

The Feb. 22 planting ceremony will center around a single tree, cultivated from a cutting of another Newton tree at the Massachusetts Institute of Technology. In time, three Newton trees will be planted outside Small Hall. William & Mary President Taylor Reveley and will be among the speakers and Provost Michael Halleran will attend.

The trees will be William & Mary’s second tangible link to the life and work of Newton. The Special Collections Research Center of Swem Library is home to a first-edition 1687 copy of Newton’s master work Philosophiæ Naturalis Principia Mathematica. The Swem Principia will be on display inside Small Hall during Newton Day activities.

Newton Day is being coordinated by physicists Marc Sher and Joshua Erlich. Sher notes that the apple story relates to Newton’s conception of universal gravitation—set forth in the Principia—in which Newton asserted that the same force that pulled an apple towards the center of the earth was also responsible for keeping earth’s moon in orbit.

“I can think of very few other discoveries that caused such a shift in the way our world understood the universe,” said Erlich, an associate professor of physics. “Before the universal law of gravitation, people tried to assign rules to the motions of celestial bodies and there were other rules for stuff that happens on earth. Newton made a great connection, a great unifying principle. It demonstrated mathematically that the motion of the moon around the earth could be explained by a single force law—the same one that governs the falling of an apple to the ground.”

Both Sher and Erlich say that the precise role of the apple is hard to pin down. “The apple tree was mentioned in the memoirs of Newton, written by William Stukeley, and was reportedly spoken of by Newton to others,” Erlich said. The apple was used as an example and it might have been an inspiration, “But it didn’t hit Newton on the head,” Sher said. “Somebody just made that up.”

Whatever its role in the conception of universal gravitation, Newton’s apple grew on a tree of variety known to horticulturalists as the Flower of Kent. Martha Case says the Flower of Kent is one of the more venerable among the thousands of apple varieties. The fruit are rather subfusc when compared to Jonagolds, Romas, Mutsus and other apples popular today.

“It’s green, but it doesn’t look like a Granny Smith,” Case said.

The three trees to be planted outside of Small Hall are often described as “descendants,” of Newton’s inspirational tree, but Case said it’s more proper to think of them as clones of the original tree. She says that if you allow for the minute changes accumulated over a few hundred years of natural mutations, the William & Mary trees are genetically identical to the tree that Isaac Newton saw.

The William & Mary trees were obtained from cuttings from a Newton tree at MIT, grafted onto rootstock. Grafting is the most common method of propagating apple varieties. MIT got its Newton cuttings from a tree in Britain’s Royal Botanical Gardens.

Sher asked Case, the College Conservator of Botanical Collections and an associate professor in William & Mary’s Department of Biology, to arrange for the biological needs of the cuttings. She grew up in the apple-rich country of northwestern Michigan and immediately realized she would need the help of a specialist to make sure the Flower of Kent would thrive in the heavy clay soil of the hot, swampy Virginia Peninsula.

“I’m a botanist, but not a horticulturalist,” she explained. Seeking an “apple person,” she sought the help of Jim Orband, a retired Virginia Cooperative Extension agent who provided a list of Virginia apple growers who might be able to help her. “My eyes went immediately to one name; it was Bill Mackintosh. Mackintosh, you know—like the apple?”

Mackintosh raises a number of apple varieties on his farm in Berryville, Va. He and Orband worked with Case on choosing the proper rootstock, preparing the soil and everything needful to give the Flowers of Kent a good start outside Small Hall. Mackintosh grafted the MIT cuttings onto rootstock and kept the trees at his orchard until time for planting.

Among the requirements for our Newton trees is the planting of more apple trees. Case explained that apples have evolved a biological mechanism that prevents self-pollination, an evolutionary defense against inbreeding. To bear fruit, the Newton trees will need to have a couple of other apple trees—selected from varieties known to pollinate the Flower of Kent—planted nearby.

“They don’t have to be really close, just within eyesight would be ideal,” Case said. “There are a number of apple and crab apple trees on campus, but we do not know if they are varieties that could cross with the Flower of Kent.”

 Case says we won’t see anything resembling leafy splendor for quite some time; the plantings are known as “whips,” which accurately depict their short, switch-like appearance. They’ll need quite a bit of care, too. Case said that young apple trees are at risk from dangers that range from fungal diseases to the deer that strip foliage from a mulberry tree outside Small Hall as far up as they can reach.

There’ll be a bench placed by the trees to accommodate anyone wanting to sit and contemplate universal gravitation. You’ll be sitting for a while, though, before an apple drops on your head—Case says it will be at least three years, and probably more, before our Newton trees bear fruit.

Newton Day’s dramatic presentation was extracted from Sobel’s book A More Perfect Heaven: How Copernicus Revolutionized the Cosmos. Liz Wiley, associate professor of theatre at William & Mary, has arranged a presentation of the play, titled And the Sun Stood Still. Wiley said the presentation will be a staged reading.

“The actors will be sitting onstage with music stands in front of them,” Wiley said. “But that doesn’t mean the audience won’t see a lot of drama.”

The all-student cast is made up of Erin McIntyre '15, Ricky Portner '14, Eliza Scheibe '16, Barclay Sparrow '17, Jason A. Via '15, and Shaan Sharma '15, “who is a physics major, by the way,” Wiley notes.

She explained that much of the action centers around an imagined exchange between Nicolaus Copernicus and a Polish bishop. The bishop is already feeling under siege from the agitations of Martin Luther, Wiley said, and heliocentrism—the global warming controversy of its day—is an inconvenient truth that the church just does not need.

“Anything that was the remotest bit controversial, like Copernicus’s view of the solar system—that the planets revolve around the sun—the bishop wants to keep quiet,” Wiley said.

The plot thickens with the arrival of Rheticus, a mathematician from Whittenberg who gets into a street scuffle with Copernicus and ends up asking to be his pupil. Meanwhile, the church fathers have developed suspicions that a woman Copernicus describes as a “housekeeper” might actually be his mistress. Their suspicions put more pressure Copernicus, who is already in hot water for his advocacy of heliocentrism.

“And I won’t tell you how it ends,” Wiley said. “You’ll have to come see it.”