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A !pipette! may consist of a narrow tube, in the middle of which is blown a bulb of a capacity a little less than that which it is desired to measure by the pipette; or it may be a miniature burette, without the stopcock or rubber tip at the lower extremity. In either case, the flow of liquid is regulated by the pressure of the finger on the top, which governs the admission of the air.
These are the principal passages which antiquity furnishes, relative to the medicinal effects of music; in considering which, reliance is placed on the judgment of M. Burette, whose opinions will come with the more weight, as he had not only long made the music of the ancients his particular study, but was a physician by profession.
It was I who told him of the chamber on the fourth story, knowing he would be a good neighbor for you." "But," said Rudolph, "who placed your daughter with the notary?" "When my wife was taken sick, I had said to Madame Burette, the pawnbroker, who lives in this house, that Louise wished to go to service to aid us.
"In filling it with must, raise the fluid in the same way, until it comes up to the line indicated at B, and then empty into the mixing bottle. "The burette consists of two hollow tubes of glass.
Add two drops of phenolphthalein solution, and run in alkali from the burette until the solution is pink; add acid from the other burette until the pink is just destroyed, and then add 0.3 cc. Heat the solution to boiling for three minutes. If no color reappears during this time, complete the titration in the hot solution.
It is best to wash out a burette at least three times with small portions of a solution, allowing each to run out through the tip before assuming that the burette is in a condition to be filled and used. It is, of course, possible to dry measuring instruments in a hot closet, but this is tedious and unnecessary.
With respect to the delay which must take place during the titration in order to give the precipitate time to fall, it is advantageous, in order to save time, to work with several samples; but it is, in such a case, desirable to have a separate burette for each sample, in order to avoid noting every addition of the chameleon solution and afterward adding them up.
From the volumes of the solutions used, after applying corrections for burette readings, and, if need be, for the temperature of solutions, calculate the value of the ferrous solution in terms of the oxidizing solution.
Wash down the sides of the beaker with a little distilled water if the solution has spattered upon them, return the beaker to the acid burette, and add acid to restore the pink; continue these alternations until the point is accurately fixed at which a single drop of either solutions served to produce a distinct change of color.
"I must say you had some luck, getting on board the barge," said Calabash; "look here, famous shawls; three real silk! Do look, mother?" "Burette will give at least five hundred francs for the whole," said the widow, after a close examination. "Then it must be worth at least fifteen hundred francs," said Nicholas, "but a receiver is as bad as a thief! Bah! I do not know how to cheat.
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