The following text may have been generated by Optical Character Recognition, with varying degrees of accuracy. Reader beware!

vviii Ier air conditioning can be de- fined as the use of mechanical means for the removal of dust and dirt from 'the air; the circulation of warmn air, and the addition of moisture to the air* in the, home. Let us consider 'the -vital question of humidityj, and its importance in relation to the heating of homes., First,,of ail, it« must be recognized that the. colder the temnperature of the air, the smaller its capacity for holding moisture. As an. ex- ample, air at zéro cannot hold more than one-haîf a. grain of moisture per cubic.,fdjot, while the samie air heated to 70, dégrées holds eight grains per. cubic foot,. or sixteen' times 'mor&e. It is very evident'.then that with outdoor temperature at zero, andý an indoor temperature of 70 ;degrees, there is a serlous de- flciency. in the rnoisture content of the indoor air. -Humidities aro spoken of in terms of -relative humîidities," rneaning in plaint language the percentage of that. total amnount of mnoisture that the air can hold. Air at 70 degrecs; as .stated hefore, can1 hold olyeight grains of moisture per; cubic foot, and so when we admit zero air, with a haif grain of moisture per* cubic foot, we have only one-sixteenth.' orJ approximately six percent relative humid- ty. This is drier air than exists. in axiY1 of the deserts of the world, and it is ntýcessarÉy to add mnoisture. 1icssary wtenave adéquate air vîrcuzla- tien, chànging the air in the conditionied rooms at least, five times per hour. Varjous methods of combining residen- tial heating and -air conditioning are avail- able today, the so-called Split System be-' ing the mhost modern and fle3iîble., High temperature Hot Water,.,circulated by mneans of a pump, la, the preferred heat- îng mredîum. the, boiler being fired by coal, ou lor gas. Radiation, of either the concealed conw vector type, or the mhodern siender tube type. is used te heat ,ail Bath - Rooms. Toilets. Kitchens, Service Quarters and GaraLee. Conditioned- air Is s.ubplied to al other roéms and bedrôoms through a systern of neat rectangular métal ducts and small registers:set in the wrall. An Air Conditionling unit is connected te the boler and hot water is circulated throueh. the couls, by means of. an electrically driven pump. Various meatis -et- addin .g moisture. te the air are incorporated in this unit, thie tyrne generally used being stnray nez- zies which atomnize the wý.ater. This brings %,ousands of small globules of water into * 1Ttma1te conftact~t ihthe air al0owng it to abscrb the requisite amourit of mois- t4ire. Thiq unit is also equipped with rnea.ns off i trn-the dust from the air, bv' the use of filters :which are discarded when dust laden and replaced \with new ones. Several installations, embodying these features. have been .designed and in- stalied by us in new houses and in homes that have been remodeled in the North Shiore territories during the past few v'ears. IZ, ~4rcLtecLi . Z litei r C1~enhi ~i~r~... FOR'THE MODERN HOME USE S U NTILE A REAL CLAY TILE One of the interesting tendencies of, con- t.emporary architecturai design. is the growing use of. brickwork for the ex- pression of decorative detail. Besides rnaking the perfect wall,' brick 8810 B3RONX AVE. NILES CENTER 462 ASSOCIATION) HCAODISTRICT 605 Builders Bldg. Chieago, Ii. uroipectu'ie