Jun 152017
 

This date in 1752 is the traditional date set for Ben Franklin’s kite flying experiment meant to prove that lightning is electricity. If he had performed the experiment as commonly thought of, and depicted, he would almost certainly have been electrocuted.  He was much more cautious, however, and it’s worth discussing Franklin and electricity on this date because what he discovered led to new directions for science. First, I will admit that I have already discussed this topic briefly here: https://www.bookofdaystales.com/benjamin-franklin/  This is what I said:

According to the canonical tale, Franklin realized the dangers of using conductive rods and instead used a kite. According to the legend, Franklin kept the string of the kite dry at his end to insulate him while the rest of the string was allowed to get wet in the rain to provide conductivity. A house key was attached to the string and connected to a Leyden jar (a primitive capacitor), which Franklin assumed would accumulate electricity from the lightning. The kite wasn’t struck by visible lightning (had it done so, Franklin would almost certainly have been killed) but Franklin did notice that the strings of the kite were repelling each other and deduced that the Leyden jar was being charged. Franklin reportedly received a mild shock by moving his hand near the key afterwards, because as he had estimated, lightning had negatively charged the key and the Leyden jar, proving the electric nature of lightning.

Fearing that the test would fail, or that he would be ridiculed, Franklin took only his son to witness the experiment, and then published the accounts of the test in third person. The standard account of Franklin’s experiment was disputed following an investigation and experiments based on contemporaneous records by science historian Tom Tucker, the results of which were published in 2003. According to Tucker, Franklin never performed the experiment, and the kite as described is incapable of performing its alleged role. Further doubt about the standard account has been cast by an investigation by the television series MythBusters. The team found evidence that Franklin would have received a fatal current through his heart had the event actually occurred. Nevertheless, they confirmed that certain aspects of the experiment were feasible – specifically, the ability of a kite with sufficiently damp string to receive and send to the ground the electrical energy delivered by a lightning strike.

Now let’s look deeper.

Franklin started exploring the phenomenon of electricity in 1746 when he saw some of Archibald Spencer’s lectures using static electricity for illustrations. Franklin proposed that “vitreous” and “resinous” electricity were not different types of “electrical fluid” (as electricity was called then), but the same “fluid” under different pressures. He was the first to label them as positive and negative respectively, and he was the first to discover the principle of conservation of charge. In 1748 he constructed a multiple plate capacitor, that he called an “electrical battery” (not to be confused with Volta’s pile) by placing eleven panes of glass sandwiched between lead plates, suspended with silk cords and connected by wires.

In 1750, he published a proposal for an experiment to prove that lightning is electricity by flying a kite in a storm that appeared capable of becoming a lightning storm. On May 10, 1752, Thomas-François Dalibard of France conducted Franklin’s experiment using a 40-foot-tall (12 m) iron rod instead of a kite, and he extracted electrical sparks from a cloud. On June 15 Franklin may possibly have conducted his well-known kite experiment in Philadelphia, successfully extracting sparks from a cloud, but there is no definitive evidence for this. However we do know that Franklin did conduct kite experiments around this time, although the results were not written up (with credit to Franklin) until Joseph Priestley’s 1767 History and Present Status of Electricity. Franklin was careful to stand on an insulator, keeping dry under a roof to avoid the danger of electric shock. Prof. Georg Wilhelm Richmann replicated the experiment in Russia in the months following Franklin’s experiment and was, indeed, killed by electrocution.

In his writings, Franklin indicates that he was aware of the dangers and offered alternative ways to demonstrate that lightning was electrical, as shown by his use of the concept of electrical ground. If Franklin ever did perform the experiment he proposed he certainly did not do it in the way that is often described—flying the kite and waiting to be struck by lightning. He did however use a kite to collect some electric charge from a storm cloud to prove that lightning was electrical. On October 19 in a letter to England with directions for repeating the experiment, Franklin wrote:

When rain has wet the kite twine so that it can conduct the electric fire freely, you will find it streams out plentifully from the key at the approach of your knuckle, and with this key a phial, or Leyden jar, may be charged: and from electric fire thus obtained spirits may be kindled, and all other electric experiments [may be] performed which are usually done by the help of a rubber glass globe or tube; and therefore the sameness of the electrical matter with that of lightening completely demonstrated.

Franklin’s electrical experiments led to his invention of the lightning rod. He noted that conductors with a sharp rather than a smooth point could discharge silently, and at a far greater distance. He surmised that this could help protect buildings from lightning by attaching “upright Rods of Iron, made sharp as a Needle and gilt to prevent Rusting, and from the Foot of those Rods a Wire down the outside of the Building into the Ground; … Would not these pointed Rods probably draw the Electrical Fire silently out of a Cloud before it came nigh enough to strike, and thereby secure us from that most sudden and terrible Mischief!” Following a series of experiments on Franklin’s own house, lightning rods were installed on the Academy of Philadelphia (later the University of Pennsylvania) and the Pennsylvania State House (later Independence Hall) in 1752.

In recognition of his work with electricity, Franklin received the Royal Society’s Copley Medal in 1753, and in 1756 he became one of the few 18th-century North Americans elected as a Fellow of the Society. He received honorary degrees from Harvard and Yale universities. The cgs unit of electric charge has been named after him: one franklin (Fr) is equal to one statcoulomb.

Franklin advised Harvard University in its acquisition of new electrical laboratory apparatus after the complete loss of its original collection, in a fire which destroyed the original Harvard Hall in 1764. The collection he assembled would later become part of the Harvard Collection of Historical Scientific Instruments, now on public display in its Science Center.

According to Michael Faraday, Franklin’s experiments on the non-conduction of ice are worth mentioning, although the law of the general effect of liquefaction on electrolytes is not attributed to Franklin. However, as reported in 1836 by A. D. Bache of the University of Pennsylvania, the law of the effect of heat on the conduction of bodies that are otherwise non-conductors, for example, glass, could be attributed to Franklin. Franklin writes, “A certain quantity of heat will make some bodies good conductors, that will not otherwise conduct …And water, though naturally a good conductor, will not conduct well when frozen into ice.”

Franklin took a great deal of interest in the food products grown in Britain and North America, generally expressing a preference for the latter.  He did, however, send seeds of kale (which he called “Scotch cabbage”) and rhubarb to friends back home. I suspect he was more interested in the medicinal properties of the roots of rhubarb than the food uses of the stalks. In return he asked his wife to send him apples and cranberries which she sent by the barrel load !! He could get apples in England, of course, but he preferred American Newton pippins for roasting over the apples he could find there. Cranberries of several species are indigenous to all northern temperate regions, but they did not catch on as a domesticated species in Europe in the way that they did in North America. Even in the United States they’re hard to find uncooked these days except around Thanksgiving; most are commercially processed into juice, sauces, and jellies. If you can find plain cranberries you might consider making a tart. Here’s one idea using a custard filling and quite a lot of brown sugar to counter the sourness of the cranberries. I generally use a prepared tart shell out of laziness, but you can make your own pastry if you wish.

Cranberry Custard Tart

Ingredients

9” tart crust
1 ½ cups granulated sugar
¼ cup water
2 cups cranberries (10 oz)
2 large eggs
½ cup brown sugar
1 ½ tsp all-purpose flour
¼ cup light cream
½ tsp almond extract
confectioners’ sugar

Instructions

Preheat the oven to 350°F/175°C.

Blind bake the tart shell by lining it with foil and filling with pie weights or dried beans. Bake the tart shell for about 30 minutes, until the rim is lightly golden. Remove the foil and weights and bake for another 5 minutes, until it is lightly golden all over. Set the tart pan on a wire rack.

Increase the oven temperature to 375°F/190°C

Meanwhile, make the filling in a medium saucepan by combining the granulated sugar with the water and cook over moderately high heat, stirring, until the sugar dissolves. Add the cranberries, cover and cook over moderate heat for 3 minutes, stirring once or twice. Remove the pan from the heat and let the cranberries cool to room temperature. Drain the cranberries well and reserve the cranberry syrup.

In a medium bowl, make a custard by beating the eggs with the brown sugar and flour. Whisk in the light cream and the almond extract. Spread the cranberries in the tart shell. Drizzle 1 tablespoon of the reserved cranberry syrup over the cranberries, then pour in the almond custard.

Bake the tart in the lower third of the oven until a skewer inserted in the center comes out clean, 16 to 18 minutes. Transfer the tart in the pan to a wire rack to cool completely, at least 2 hours. Dust with confectioners’ sugar.

Jan 172016
 

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Today is the birthday (1706) of Benjamin Franklin, one of the so-called Founding Fathers of the United States, a renowned polymath – author, printer, political theorist, politician, freemason, postmaster, scientist, inventor, civic activist, statesman, and diplomat. As a scientist, he was a major figure in the American Enlightenment and the history of physics for his discoveries and theories regarding electricity. As an inventor, he is known for the lightning rod, bifocals, and the Franklin stove, among other inventions. He facilitated many civic organizations, including Philadelphia’s fire department and a university.

Franklin earned the title of “The First American” for his early and indefatigable campaigning for colonial unity, first as an author and spokesman in London for several colonies. As the first United States ambassador to France, he exemplified the emerging American nation (famous for his “natural” appearance by arriving at the French court for the first time showing his natural hair and not in a powdered wig). Franklin was foundational in defining the American ethos as a marriage of the practical values of thrift, hard work, education, community spirit, self-governing institutions, and opposition to authoritarianism both political and religious, with the scientific and tolerant values of the Enlightenment.

Franklin became a successful newspaper editor and printer in Philadelphia, the leading city in the colonies. With two partners he published the Pennsylvania Chronicle, a newspaper that was known for its revolutionary sentiments and criticisms of British policies. He became wealthy publishing Poor Richard’s Almanack and The Pennsylvania Gazette.

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He played a major role in establishing the University of Pennsylvania and was elected the first president of the American Philosophical Society. Franklin became a national hero in America when as agent for several colonies he spearheaded the effort to have Parliament in London repeal the unpopular Stamp Act. An accomplished diplomat, he was widely admired among the French as American minister to Paris and was a major figure in the development of positive Franco-American relations. His efforts to secure support for the American Revolution by shipments of crucial munitions proved vital for the war effort.

For many years he was the British postmaster for the colonies, which enabled him to set up the first national communications network. He was active in community affairs, colonial and state politics, as well as national and international affairs. From 1785 to 1788, he served as governor of Pennsylvania. Toward the end of his life, he freed his own slaves and became one of the most prominent abolitionists.

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His colorful life and legacy of scientific and political achievement have seen Franklin honored on coinage and the $100 bill; warships; the names of many towns; counties; educational institutions; corporations; and, more than two centuries after his death, countless cultural references.

It’s impossible in a short post to run through all that Franklin accomplished, so I am going to pick a few of my favorites. I’ll begin with his invention of the mechanical glass harmonica. The use of a crystal wine glass to produce a ringing tone by rubbing a wet finger around the rim is documented back to Renaissance times. The Irish musician Richard Pockrich is typically credited as the first to play an instrument composed of glass vessels filled with differing amounts of water to produce different tones. In the 1740s, he performed in London but his career was cut short by a fire in his room, which killed him and destroyed his apparatus. Edward Delaval, extended Pockrich’s experiments by creating a set of glasses that were better tuned and easier to play. During the same decade, Christoph Willibald Gluck also attracted attention playing a similar instrument in England.

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Franklin invented a radically new arrangement of the glasses in 1761 after seeing Edmund Delaval play in Cambridge in England in May of 1761. Franklin worked with London glassblower Charles James to build one, and it had its world premiere in early 1762, played by Marianne Davies. In Franklin’s treadle-operated version, 37 bowls were mounted horizontally on an iron spindle. The whole spindle turned by means of a foot pedal. The sound was produced by touching the rims of the bowls with water moistened fingers. Rims were painted different colors according to the pitch of the note: A (dark blue), B (purple), C (red), D (orange), E (yellow), F (green), G (blue), and accidentals were marked in white. With the Franklin design, it is possible to play ten glasses simultaneously if desired, a technique that is very difficult if not impossible to execute using upright goblets.

Mozart, Beethoven, Richard Strauss, and more than 100 other composers composed works for the glass harmonica. Some pieces survive in the repertoire through transcriptions for more conventional instruments. Camille Saint-Saëns used this instrument in his The Carnival of the Animals (in movements 7 and 14). Donizetti originally specified the instrument in Lucia di Lammermoor as a haunting accompaniment to the heroine’s “mad scenes”, though before the premiere he was required by the producers to rewrite the part for two flutes. Here’s Mozart’s Adagio in C Major for glass harmonica (K617a).

Many storybooks tell of Franklin flying a kite with a key attached in a storm to attract lightning to prove it is electrical in nature. Such an experiment was carried out in May 1752 at Marly-la-Ville in northern France by Thomas-François Dalibard. An attempt to replicate the experiment killed Georg Wilhelm Richmann in Saint Petersburg in August 1753, thought to be the victim of ball lightning. Franklin himself is said to have conducted the experiment in June 1752, supposedly on the top of the spire on Christ Church in Philadelphia. However, doubts have been expressed about whether the experiment was actually performed.

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According to the canonical tale, Franklin realized the dangers of using conductive rods and instead used a kite. According to the legend, Franklin kept the string of the kite dry at his end to insulate him while the rest of the string was allowed to get wet in the rain to provide conductivity. A house key was attached to the string and connected to a Leyden jar (a primitive capacitor), which Franklin assumed would accumulate electricity from the lightning. The kite wasn’t struck by visible lightning (had it done so, Franklin would almost certainly have been killed) but Franklin did notice that the strings of the kite were repelling each other and deduced that the Leyden jar was being charged. Franklin reportedly received a mild shock by moving his hand near the key afterwards, because as he had estimated, lightning had negatively charged the key and the Leyden jar, proving the electric nature of lightning.

Fearing that the test would fail, or that he would be ridiculed, Franklin took only his son to witness the experiment, and then published the accounts of the test in third person. The standard account of Franklin’s experiment was disputed following an investigation and experiments based on contemporaneous records by science historian Tom Tucker, the results of which were published in 2003. According to Tucker, Franklin never performed the experiment, and the kite as described is incapable of performing its alleged role. Further doubt about the standard account has been cast by an investigation by the television series MythBusters. The team found evidence that Franklin would have received a fatal current through his heart had the event actually occurred. Nevertheless, they confirmed that certain aspects of the experiment were feasible – specifically, the ability of a kite with sufficiently damp string to receive and send to the ground the electrical energy delivered by a lightning strike.

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Franklin was purportedly the master of the pithy aphorism. “Early to bed and early to rise, makes a man healthy wealthy and wise,” for example, is found in the 1735 edition of his Poor Richard’s Almanack, and is typical in that its attribution to Franklin is only partially accurate. Yes, he printed the saying; no, he did not create it. The earliest known record of a proverb that approximates to Franklin’s comes from The Book of St. Albans, printed in 1486:

As the olde englysshe prouerbe sayth in this wyse. Who soo woll ryse erly shall be holy helthy & zely.

The Middle English word zely comes down to us now as “silly,” and could mean “foolish” in the 15th century. But it could also mean “fortunate.” “Holy helthy & zely” probably meant “wise, healthy and fortunate” and in some form came down to Franklin. It can be found in John Clarke’s Paroemiologia Anglo-Latina in 1639:

Earely to bed and earely to rise, makes a man healthy, wealthy, and wise.

Later U.S. commentators have had some fun at Franklin’s expense. In 1928, Carl Sandburg suggested that ‘Early to bed and early to rise and you never meet any prominent people’. In the New Yorker, February 1939, James Thurber turned it round:

Early to rise and early to bed makes a male healthy and wealthy and dead.

In a letter to Jean-Baptiste Leroy, dated 1789, Franklin wrote:

Our new Constitution is now established, and has an appearance that promises permanency; but in this world nothing can be said to be certain, except death and taxes.

The fact that Franklin doubted the permanence of the Constitution is interesting in itself; but we should also note that the notion of the certainty of only “death and taxes” did not originate with Franklin. It comes from Daniel Defoe’s The Political History of the Devil (1726):

Things as certain as death and taxes, can be more firmly believ’d.

I like this saying attributed to Franklin a lot:

Tell me and I forget. Teach me and I remember. Involve me and I learn.

But he never said it. Likewise I once had a T-shirt with this saying attributed to Franklin:

Beer is proof that God loves us and wants us to be happy.

Franklin never said this either, but he did say this about wine:

We hear of the conversion of water into wine at the marriage in Cana, as of a miracle. But this conversion is, through the goodness of God, made every day before our eyes. Behold the rain which descends from heaven upon our vineyards, and which incorporates itself with the grapes to be changed into wine; a constant proof that God loves us, and loves to see us happy!

Franklin has a great deal to say about food, and, in particular, promoted native American cultigens in Europe where they were largely disapproved of. Both potatoes and tomatoes were considered by some to be poisonous. He is credited, also, with introducing tofu, rhubarb, and kale into the U.S. (in the latter 2 cases sending seeds from Scotland). Here’s a defense of American cuisine from a 2 January 1766 letter:

Pray let me, an American, inform the gentleman, who seems ignorant of the matter, that Indian corn, take it for all in all, is one of the most agreeable and wholesome grains in the world; that its green leaves roasted are a delicacy beyond expression; that samp, hominy, succotash, and nokehock, made of it, are so many pleasing varieties; and that johny or hoecake, hot from the fire, is better than a Yorkshire muffin – But if Indian corn were so disagreeable and indigestible as the Stamp Act, does he imagine that we can get nothing else for breakfast? – Did he never hear that we have oatmeal in plenty, for water gruel or burgoo; as good wheat, rye and barley as the world affords, to make frumenty; or toast and ale; that there is every where plenty of milk, butter, and cheese; that rice is one of our staple commodities; that for tea, we have sage and bawm in our gardens, the young leaves of the sweet hickery or walnut, and above all, the buds of our pine, infinitely preferably to any tea from the Indies … Let the gentleman do us the honor of a visit in America, and I will engage to breakfast him every day in the month with a fresh variety.

Lots to choose from here, but I pick succotash. The word succotash may come from Narragansett sohquttahhash meaning “broken corn kernels,” or misckquatash meaning “boiled corn kernels.” In any event, it is a common dish in the U.S. South. The primary ingredients are freshly hulled corn kernels and either lima beans or other shell beans. The two together are high in amino acids. Add squash and you have complete protein. There’s hundreds of versions of succotash. Here’s how I was taught to make it in coastal North Carolina. I’ll leave you to worry about quantities and such. This recipe uses fresh ingredients, but a lot of contemporary cooks use canned vegetables and simply mix them and heat them through. Occasionally a Southern cook will bake succotash with a pastry top.

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Succotash

Using a sharp knife scrape the whole kernels from corn cobs. Add an equal quantity of lima beans. Seed and dice some tomato and bell pepper (green or red or both), and add them to the mix. Place the vegetables in a large pot, cover with water, and simmer. Length of cooking time is cook’s choice. I prefer the vegetables to be al dente, but my Southern friends used to boil them to death.

Succotash is normally served warm as a side dish, but you can also serve it chilled, dressed with a little vinegar, as a salad.

 

 

Jun 152013
 

wind1 Jack and Jill  windmill dutch

windmills  Windmills_Overlooking_Hora_Dodecanese_Leros_Greece

windmill-greece  wind3

wind7  wind4

wind5  wind-turbine-1  windmills_california-1   wind8

Today is Global Wind Day, a worldwide event celebrated on 15 June since 2007 (called simply Wind Day at the time).  The purpose of the celebration is to enjoy and learn about the many uses of wind power. Harnessing the wind is an expanding green technology increasingly used to reduce global dependence on fossil fuels, and to limit the harmful effects of the release of the products of combustion into the atmosphere.  But with little effort we can all come up with the many uses of wind power that affect our lives both for practical purposes and for pleasure.

I have long had a fascination with different ways to harness the wind from kite flying to sail boats, but nothing rivals windmills for me, as the gallery at the head of this post will testify.  Windmills of one sort or another have been employed to convert wind power into usable energy since antiquity, the main uses being grinding food materials (as the “mill” part suggests) and pumping water.  The chief problem to overcome in all employment of the wind is its erratic nature, both in terms of force and direction.  Every sailor (“user of sails”) knows the frustration of trying to sail a boat when there is no wind.  Fossil fuel powered ships replaced sailing ships in the nineteenth century for precisely this reason. The regions of the Pacific and Atlantic Oceans around the equator, known as the doldrums, were a particular hazard for sailing ships that might be becalmed there for days or weeks.  Coleridge’s description in the Rhyme of the Ancient Mariner is justly famous:

Day after day, day after day,
We stuck, no breath no motion;
As idle as a painted ship
Upon a painted ocean.

Talk about being in the doldrums!

Windmills can, of course suffer the same fate, and are only a truly effective technology in regions of the world where regular winds can be expected.  This is one of the major problems with modern wind farms that are springing up in many parts of the world.  70% of the land mass of the world has low wind speed, but ingenious new technologies are emerging to cope with the problem.  In Thailand, for example, there was a rush to import windmills a few years ago when the country had a serious energy problem, only to see the European giants sit idle like unwanted statues until a storm came (or a Thai version of Don Quixote showed up).  But local engineers have since designed small low wind speed turbines that by themselves produce small amounts of electricity, but when dotted around in large numbers effectively feed the power grid.

As a former sprinter, cross-country runner, and ever frequent flyer, I know the value of having the wind in your favor.  So I wish all of my readers a happy Global Wind Day. “May the wind be always at your back.”

Windmill cookies are a great favorite in Holland.  Usually they are made using special wooden molds, which I would guess most of you do not have lying around in that kitchen drawer full of utensils you never use.  Admit it – we all have one of those drawers.  But here’s a recipe for windmill cookies that does not require special equipment.  They are nice and spicy, and shaped like the sails of a windmill.

windmill cookies

Dutch Windmill cookies

Ingredients

¼  cup (.6 dl) sour cream
½ (2.5 g) teaspoon baking soda
1 ¾ cups (225 g) all-purpose flour
½ (2.5 g) teaspoon salt
½ (2.5 g) teaspoon ground cinnamon
½ (2.5 g) teaspoon ground nutmeg
¼ (1.2 g) teaspoon ground cloves
1 cup (220 g) firmly packed brown sugar
½ cup (113 g) unsalted butter, softened
sliced almonds

Instructions:

Pre-heat oven to 350°F/175°C.

Stir the sour cream and baking soda together in small bowl and set aside.

Combine the flour, salt, cinnamon, nutmeg and cloves in medium bowl.

Combine the brown sugar and butter in a large bowl. Beat at medium speed until creamy.

Reduce the speed to low and add the sour cream mixture. Beat until well mixed.

Add the flour and spice mixture. Continue beating to form a smooth dough.

Divide the dough in half. Wrap  half in plastic food wrap and refrigerate.

Roll out the remaining half of dough, on a lightly floured surface, to an 8 ¾ inch (22.25 cm) square.

Cut 7 strips horizontally, and then 7 strips vertically to create 49 squares. Cut each square diagonally to create 98 triangles.

For each cookie, place 4 triangles on to ungreased cookie sheets (overlapping the tips in the middle as in the photo). Place sliced almonds in center, pressing down lightly to make sure the triangles make one cookie. Repeat with the remaining triangles (you will have one bit left over which you can bake and eat in the kitchen without anyone knowing).

Bake for 7 to 11 minutes or until golden.

Let cool 2 minutes on the cookie sheets, then remove the cookies to a wire cooling rack.

Repeat this process with the second batch of dough.

Yield: 4 dozen cookies