Quinquet and Lange was introduced, and much admired for its fplendor; but a general enquiry was made, whether the oil it confumed was not in proportion to the light it afforded, in which cafe there would be no faving in the ufe of it. No one present could fatisfy us in that point, which all agreed ought to be known, it being a very desirable thing to leffen, if poffible, the expence of lighting our apartments, when every other article of family expence was fo much augmented.

I was pleased to see this general concern for œconomy; for I love economy exceedingly.

I went home, and to bed, three or four hours after midnight, with my head full of the fubject. An accidental fudden noife waked me about fix in the morning, when I was furprised to find my room filled with light; and I imagined at first, that a number of those

lamps had been brought into it: but, rubbing my eyes, I perceived the light came in at the windows. I got up and looked out to fee what might be the occafion of it, when I saw the fun just rifing above the horizon, from whence he poured his rays plentifully into my chamber, my domestic having negligently omitted the preceding evening to close the fhutters.

I looked at my watch, which goes very well, and found that it was but fix o'clock; and still thinking it fomething extraordinary that the fun fhould rise fo early, I looked into the almanack, where I found it to be the hour given for his rifing on that day. I looked forward too, and found he was to rife ftill earlier every day till towards the end of June; and that at no time in the year he retarded his rifing fo long as till eight o'clock. Your readers, who with me have never feen any figns of funshine before

before noon, and feldom regard the aftronomical part of the almanack, will be as much astonished as I was, when they hear of his rifing fo early; and efpecially when I affure them, that he gives light as foon as he rifes. I am convinced of this. I am certain of my fact. One cannot be more certain of

faw it with my own eyes.

any fact.

fact. I

And having

repeated this obfervation the three following mornings, I found always precifely the fame refult.

Yet fo it happens, that when I fpeak of this discovery to others, I can easily perceive by their countenances, though they forbear expreffing it in words, that they do not quite believe me. One, indeed, who is a learned natural philofopher, has affured me, that I must certainly be mistaken as to the circunistance of he light coming into my room; for it being well known, as he fays, that there could be no light abroad at that hour,

it follows that none could enter from without; and that of confequence, my windows being accidentally left open, inftead of letting in the light, had only ferved to let out the darkness: and he ufed many ingenious arguments to fhew me how I might, by that means, have been deceived. I own that he puzzled me a little, but he did not fatisfy me; and the fubfequent obfervations I made, as above mentioned, confirmed me in my first opinion.

This event has given rise, in my mind, to several serious and important reflections. I confidered that, if I had not been awakened fo early in the morning, I should have flept fix hours longer by the light of the fun, and in exchange have lived fix hours the following night by candle-light; and the latter being a much more expenfive light than the former, my love of economy induced. me to mufter up what little arithmetic

I was

I was mafter of, and to make fome calculations, which I fhall give you, after obferving, that utility is, in my opinion, the test of value in matters of invention, and that a discovery which can be applied to no use, or is not good. for fomething, is good for nothing.

I took for the bafis of my calculation the fuppofition that there are 100,000 families in Paris, and that these families confume in the night half a pound of bougies, or candles, per hour. I think this is a moderate allowance, taking one family with another; for though I believe fome confume lefs, I know that many confume a great deal more. Then eftimating feven hours per day, as the medium quantity between the time of the fun's rifing and ours, he rifing during the fix following months from fix to eight hours before noon, and there being seven hours of course per night in which we