Radiators were placed as shown in Fig. 1 in tests 6, 7, 10, 11 and 12, and interchanged in tests 2, 3, 4 and 5 and in test 14 as shown in Fig. 1a. In test No. 1 the radiators were placed parallel to and under the windows, as shown in Fig. 1, and in test No. 2 the radiators were placed near the windows at right angles to the walls, as shown in Fig. 1a. In comparing these two tests it will be noticed that the radiators give slightly better results when placed at right angles to the walls, the actual percentage increase being about 5 per cent. In order to determine whether the furniture in the room had any effect upon the average of ten tests, shows a slightly smaller result, the average difference being about 3%, that is, the pressed-steel radiator shows a heat radiation about 3% less than might be expected from a similar type of cast-iron radiator. RELATIVE SPEED OF HEAT. It was thought that, owing to the difference in weight of the two types of radiator used in these tests, there might be an appreciable difference in the speed with which these two types of radiation would heat the rooms and the test was made in order to determine the differ ence. The cast-iron radiator used weighed 3161⁄2 lbs., while the steel radiator weighed 108.3 lbs. It is natural to suppose that a pressed-steel radiator be 74 72 70 168 tion in pounds taken at 10-minute intervals. The upper curve shows the increase in temperature in the room. The lower curves shows the condensation. The dotted line is for the cast-iron radiation and the solid line for the pressed steel. It will be noticed that the heating effect as shown by the rise in temperature of the rooms is practically the same in both rooms and apparently these tests show that the difference in weight of the two types of radiation made very little difference in the actual rise in temperature of the rooms. The condensation curve, however, shows that the cast-iron radiator had a much more rapid condensation for the first 10 minutes, about 31⁄2 times the normal, but at the end of 20 minutes this condensation had almost 56 reached the normal; by 30 minutes normal condition had been reached. In the pressed-steel radiator condensation for the first 10 minutes was about twice the normal, and at the expiration of 20 minutes the radiator had reached normal conditions of condensation. +66 164 162 60 58 54 52 150 148 46 200 Room Temperatures COMPARISON OF HIGH AND LOW RADI- A set of tests was also made to determine the heat transmission of two radiators of the pressed-steel type of different heights. The results show that with a temperature difference between the room and steam of 143° F. the coefficient of transmission for the 14-in. radiator was 1.647 for the rated surface and 1.855 for the actual surface of the radiator; for the 38-in. radiator, under similar conditions, the coefficient was 1.498 for the rated surface and 1.527 for the actual surface of the radiator. These are approximately the same results as would be expected from cast-iron radiation. Cooling Two Rooms in a Country Residence BY A. M. FELDMAN. (Presented at the Annual Meeting of the American Society of Heating and Ventilating Engineers, New York, January 20-22, 1914.) For the country residence of Mr. Paul M. Warburg at Hartsdale, N. Y., the author was called upon to provide a design for cooling the owner's bedroom and morning room, in conjunction with the installation of a small refrigerating plant by installing a cork insulated box with 300 ft. of 1 in. galvanized iron pipe in the attic immediately above the rooms. The top of the box was connected with a short duct to the roof dormer for taking in fresh air, and from the ends near the bottom two galvanized iron ducts. were connected to the ceiling registers of the two rooms as shown on the accompanying plan. Fresh air enters the top of the box, is cooled and drops by gravity through the registers to the floor of the rooms. The cooled air there moves forward and escapes through the partially opened windows, thus creating the necessary change of air for ventilation. The author took advantage of the thermostats which were installed in the rooms in connection with the heating system and connected them with driaphragm levers to control dampers in the ducts, thus providing means for automatically shutting off the cold air in case the rooms would become colder than desired. Tests showed a temperature in the rooms of about 6° F. lower than out of doors. ELEVATION OF COOLING BOX AND The cooling box is provided with two narrow but deep so-called congealing tanks filled with brine with part of the coils submerged therein. The chilled brine in these tanks furnishes enough cold storage to cool the air part of the night when the refrigerating machine is not in operation. The ammonia piping is arranged in three coils with valves as shown in the accompanying drawing. The coils are cooled by direct expansion. of ammonia. The structural details of the box are also indicated in an accompany illustration, which shows the position of the congealing coils and the location of the valves. These valves give flexibility to the system in operation, as the ammonia. monia pipes throughout the installation are welded together by means of the Goldschmidt thermit process. All the ammonia pipes and ducts are properly insulated with cork covering. The ammonia compressor is a 5-ton, twocylinder vertical machine driven by an electric motor through a short belt, with a belt tightener idler. In order not to waste it, the condensing water is pumped back to the general domestic elevated supply tank by means of a small motor-driven centrifugal pump. The water was never found to have any odor or taste of ammonia. NATION ATING Campaign for New Members. A campaign to increase the membership of the National District Heating Association has been inaugurated by the officers of the association. Members are requested to correspond with one or more of a list of prospective members sent out by the association with a view of securing their applications for associate membership. Heating and Ventilation Laws and Regulations in the United States REQUIREMENTS OF RECENTLY-ENACTED AND OTHER LAWS NOW ON THE STATUTE BOOKS IN THE VARIOUS STATES. The enactment of new heating and ventilation laws in such States as Massachusetts, Ohio and Indiana and the changes made in the requirements in some of the other States makes a review of the subject timely as well as necessary. No attempt will be made here to list the laws in the order of their passage or alphabetically by States. Such an arrangement, however, will be followed in a reprint which we shall make later, to be published as the third edition of "Ventilation Laws." In the following summary those laws which have been passed most recently are given first place. Indiana. New rules and regulations governing the construction, equipment and maintenance of sanitary features of public and parochial school buildings were passed by the Indiana State Board of Health, December 17, 1913. These rules and regulations have all the force of law, the State Board being empowered, among other things, to "regulate and prescribe the character and location of plumbing, drainage, water supply, lighting, heating and ventilation, and all sanitary features of all public buildings and institutions, * * and any violation of said rules shall be punished by a fine of not less than five nor more than fifty dollars for each offense." (Chapter 144, Acts 1909, Part of Section 6.) ** The rules take up the site for school buildings, followed by construction features. In connection with the size of class rooms, it is provided that no class room shall exceed 24 ft. in width. The ceiling shall be not less than 12 ft. nor more than 14 ft. in height. Wood ceilings shall not be used. The provisions covering heating and ventilation are extensive and include both the requirements and the methods of fulfilling such requirements. They are as follows: Heating and Ventilation: Heating and ventilating systems of all kinds shall take fresh air from outside the school building, evenly diffuse the same throughout each schoolroom during school session and withdraw foul air from said schoolroom at a minimum rate of 1,800 cu. ft. per hour for each 225 cu. ft. of said schoolroom space, regardless of outside atmospheric conditions. a. Test-The State Board of Health will test the efficiency of ventilating systems in school buildings as follows: With jacketed heaters and gravity systems, the anemometer test shall be made over the foul air vents in classrooms. With plenum systems, the anemometer test shall be made over the fresh air inlet of the fresh air room and the fresh air inlet in classrooms. With a double system of mechanican ventilation, the anemometer test shall be made at the fresh air intake and at the foul air vents in classrooms. In every test five readings shall be taken, one near each corner and one at the center of the air-opening to be tested. A deduction of 5% shall be made for a grill or register in the air opening. All tests shall be based upon the seating capacity of classrooms at 225 cu. ft. of space per pupil. Before such test shall be made by the State Board of Health, the heating and ventilating contractor shall be given notice of the time when such test is to be made. The State Board of Health will make such tests upon the written request of trustees, school boards, boards of school commissioners, county, city or state superintendents, or upon petition of ten or more patrons of the school. Plenum and Gravity Systems of Ventilation: Where plenum systems of ventilation are used, the warm air flues shall have a cross-sectional area of not less than 10 sq. in. for each occupant of the room, based on the seating capacity of the room. The vent flues shall have a cross-sectional area of not less than 10 sq. in. for each occupant of the room, based on the seating capacity of the room. Where gravity systems of ventilation are used, the warm air flues and vent flues shall each have a cross-sectional area of not less than 16 sq. in. for each occupant of the room, based on the seating capacity of the room. a. Location of Flues-In school buildings of more than one room with plenum or gravity ventilation the warm air flues and vent flues shall be on or in the inside walls of the building, and the warm air inlets and the foul air vents shall be on the same side of the room. Warm air inlets shall be located not less than 5 ft. from the floor. Wire screens of No. 8 gauge wire with 12-in. mesh may be used to cover the warm air inlets, except in rooms of such size and shape as to require the air to be deflected, in which case diffusers may be used. Four air vents shall be at the floor level, shall have a free area of not less than the cross-sectional area of the flue, and shall be clear of all obstructions. Grills or registers shall not be used in foul air |