Farrow's military encyclopedia : a dictionary of military knowledge . d precaution to verify them by a recountafter making the record. A tliermometer. with ascale of about 5° to the inch, sub-divided in quartersof a degree, is suspended in the water while weigh-ing samples and the temperature sliould be notedat each weighing. The weighings are made at tem-peratures varying with the state of the weather atthe time, and as llie density of water varies with itstemperature, the latter is noted in order that the pro-per corrections may be made. The unit adopted isdistilled water at the temperature
Farrow's military encyclopedia : a dictionary of military knowledge . d precaution to verify them by a recountafter making the record. A tliermometer. with ascale of about 5° to the inch, sub-divided in quartersof a degree, is suspended in the water while weigh-ing samples and the temperature sliould be notedat each weighing. The weighings are made at tem-peratures varying with the state of the weather atthe time, and as llie density of water varies with itstemperature, the latter is noted in order that the pro-per corrections may be made. The unit adopted isdistilled water at the temperature of (!() Fahr. The hydrometer may be employc-d to determinethe relative density of distilled and any other kind of?water. The weiglit of the hydrometer, added toits balance-weight in distilled water, at the tempera-ture of fiO, gives llie weiglit of a quantity of purestandard wat<T which is e(|ual in bulk to tlie im-mersed part of the instrument. The weight of thehydrometer, with its load, when immersed in likemanner in any other kind of water at the same tem-. perature, gives the weight of an equal bulk of thelatter: and this weight, divided by the former, givegthe multiplier for correcting the density when as-certained in any other than pure distilled or river water may be used instead of distilledwater, if its relative density be first accurately deter-mined and the proper correction be made. At thefoundries, generall}, river water is found to be snffi-cientl)- pure for use without needing any using the hydrometer, first load the pan with thegrain weights until the instrument rests at zero, andrecord the sum of these weights as the Balance nf theUydrometcr. Ne.\t, place in tlie pan the sample, to-gether with as many weights as will again bring theinstrument to its zero, and record these weights asthe Sample Balance in Ah: The difference betweenthese balances is equal to the weight of the samplein air. Then place the sample on the bulb of theinstru
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Keywords: ., bookcentury1800, bookdecade188, booksubjectmilitaryartandscience
