Daylight Shifting Time
This is the weekend we shift our clocks back to Standard time. So check your clocks, you were supposed to get up at 2:00 am and move the dials back a hour. Hope you did just that. Are you like me and enjoyed another hour of sleep this morning? But what does it really mean, this exercise in playing with all the clocks even in the car (don't forget that one). It is not really about saving daylight because that is going down here in the northern hemisphere wether we move clocks or not. It is about shifting time to morning or night. The credit of this idea is to Benjamin Franklin. Slightly edited for brevity.
Benjamin Franklin Excerpts and commentary on
the essay in Journal de Paris, on April 26, 1784
As he neared the end of his long tenure as American delegate in Paris, Benjamin Franklin felt his years. Gout and gallstones hampered his movements and left him virtually confined to his house in the Parisian suburb of Passy.
One such piece took the form of a letter to the Journal de Paris concerning the economy of lighting in the home, which Franklin wrote after attending the demonstration of a new oil lamp. In it, he parodied himself, his love of thrift, his scientific papers and his passion for playing chess until the wee hours of the morning then sleeping until midday. His friend Cadet de Vaux published the letter in the Journal on April 26, 1784, under the English title An Economical Project. Franklin began the letter by noting that much discussion had followed the demonstration of an oil lamp the previous evening concerning the amount of oil used in relation to the quantity of light produced. This he followed with details of how a great discovery of an avenue of thrift came to him.
The Parisians never woke before noon
Franklin had eventually bedded down at three or four hours past midnight but was awakened at six in the morning by a sudden noise. Surprised to find his room filled with light, Franklin at first imagined that a number of the new oil lamps were the source, but he soon perceived the light to be originating from the outside. Looking out the window, Franklin saw the sun rising above the horizon, its rays pouring through the open shutters.
"I looked at my watch, which goes very well, and found that it was but six o clock; and still thinking it something extraordinary that the sun should rise so early, I looked into the almanac, where I found it to be the hour given for his rising on that day. I looked forward too, and found he was to rise still earlier every day towards the end of June; and that no time during the year he retarded his rising so long as till eight o clock. Your readers, who with me have never seen any sign of sunshine before noon, and seldom regard the astronomical part of the almanac, will be as much astonished as I was, when they hear of his rising so early; and especially when I assure them, that he gives light as soon as he rises. I am convinced of this.
Sly Franklin claimed that a noted philosopher assured him that he was most certainly mistaken, for it was well known that "there could be no light abroad at that hour." His windows had not let the light in, but being open, had let the darkness out.
"This event has given rise in my mind to several serious and important reflections," the letter continued. Had he not been aroused at so early a morning hour, he would have slept until noon through six hours of daylight and therefore, living six hours the following night by candlelight. Realizing the latter was much more expensive than the former, he began calculating, for the sheer love of economy, the utility of his discovery -- the true test of any invention.
On the assumption that 100,000 Parisian families burned half a pound of candles per hour for an average of seven hours per day (the average time for the summer months between dusk and the supposed bedtime of Parisians), the account would stand thus:
"183 nights between 20 March and 20 September times 7 hours per night of candle usage equals 1,281 hours for a half year of candle usage. Multiplying by 100,000 families gives 128,100,000 hours by candlelight. Each candle requires half a pound of tallow and wax, thus a total of 64,050,000 pounds. At a price of thirty sols per pounds of tallow and wax (two hundred sols make one livre tournois), the total sum comes to 96,075,000 livre tournois."An immense sum," the astonished Franklin concluded, "that the city of Paris might save every year."
"You may delay,
but time will not"