A manual of home-making

To ij^ivc a fair measure of the temperature of a room, a ther- mometer should l)e plaeed about four feet from the floor, away from a stove, nuliator, or ventihition Hue and not on an out- side wall. Under certain conditions fifteen nunutes or more may be required to show the correct temperature if a thermometer is moved. Outdoor thermometer. To indicate the real temperature of outdoor air as given in the weather reports, a thermometer must I>e mounted in a specially well ventilated house or box four feet from the ground and so built as to shield tlie thermometer entirely from direct f?unlight. Nearl}' the same results may be secured Ijy placing a thentiometer in an open shady place, possibly at the north of a building, several feet away from the walls and four feet from the ground. I ^ 132 A MANUAL OF HOME-MAKING itj^ *!>' 105- t6' -«jr -lir 2J- y=n tr r-^ "5^ -1^ CHnicd tliermomekr. The usyal cliiijcal thermometer is a '*ma: mum *' thermometer, that Is, the mercury in the stem registers the highest temperature reaehed and does not return when the ther- mometer is cooled, hut nmst be shaken back before another temperature can be measured. For this rea.s€>n tlie thermometer may be removed from the mouth and read later. The usual type^ of 'Mens4ront*' thermome- ter is so made that the front of the glass tute acts as a lens mai^nifying the width of the mercur>^ thread. To read such a tliermome- ter, it should lie held in the hand and turned until the increuiy column suddenly appears magnified to eonsideraijle width. This will occur when the clear corner of the triangular tube is directly in front. The reading can then be made, remembering that the smallest th visions of the scale are usually 0°.2. The mercury should then be shaken back into the bulb by holding the thermometer firmly l>e- tween thmnb and forefinger, Imlb outward, and giving a few wry brisk shakes from the wrist, or with the ann, and then seeing that the* thermometer reads as low as OG^ F. or 35^.5 C. The thermometer should never be tapped against a hard sul>stance, as this is almost certain to break the bulb. Bath thermometers. Bath thermometers usually have their scales printed on paiyvr or milk glass contained in a large glass tube which inc]os4\s the ther- mometer capillar>\ They are often protected by a wooden cage to prevent breakage. When thus protected, it may take some time to ol>- Flo. 40.-^Com(>arisoo of CcntigrBde and Fahrenheit scaler for m«'ti8uritifs tem- perature. -"> ^-U =;r--4 I I I -i> HOUSEHOLD MEASUREMENTS AND THEIR USE 133 tain the real temperatui'e of the xvatrr unless the thermometer is kept movinR. The temf>eraturas in dilTerent parts of a tub of water may ciiiTer iiiiiQy degrees ualcss tlie water has been well mixed. A bath thermometer should be read while it is in the water because the reatlings will ehaopje veiy rapidly when the ther- mometer is taken out of wai*m water. Milk thcrtnom^krs. Milk thermometers are useful in meawuring the temperature of milk or eroaiii, for the control of pasteurizing milk, churning cream, whipping cream » and the like. These processes are best earned out at definite temperatures. Some of these milk ther- mometers are purposely made large and light bo that they will float, making their use more convenient. Candy-nmking thennmnekrs.