July,
1911
T H E J O C R ~ Y A LOF INDL’STRIAL A A T D E N G I N E E R I N G CHE,MISTRY.
The thermostat G consists of a long glass tube bent into a flat rectangular coil and fastened to a perforated brass plate resting on short legs on the bottom of the bath. I t is filled with mercury and closed a t one end. To the open end is sealed a device shown in detail in Fig. 2 . Electric connection is made with the mercury in the thermostat through the platinum wire A (Fig. 2 ) which passes through the glass wall near the double seal. The low tension current which is made and broken in the thermostat at, B which operates the relay R (Fig. I ) is taken as a shunt from the 110-volt directlighting current by connecting the ow-tension across adjacent taps on the 1,000-ohm resistance coil H. There are seven such taps along the coil and the potential difference between two adjacent ones is about 14 volts when the coil is in the I I O volt circuit. The current which actuates the sounder is made and broken b y the relay. It passes from the relay through the 32-candle power lamp I , then through the electromagnets of the sounder, and back to the line, using the 110-volt direct current. The sounder is of the usual form, rated at 5-ohms, and ‘I’ Fig. 2 . heats but very slightly when the current passes through continuously. Except for the simple device shown for supporting the rubber tube, no other change in the sounder is necessary except that, if desired, the edges of the lever may be beveled so that the rubber tube is closed more easily. Small condensers, not shown, situated in the bases of the sounder and relay are used in lessening sparking when the currents are opened and closed in the thermostat and the relay respectively. If cooling water is added a t a rate very slightly more rapid than is necessary, the temperature is controlled with great exactness. Under these conditions, however, not enough cool water would be supplied should the room temperature rise considerably. On the other hand, if cold water is added too rapidly the bath becomes much undercooled a t each addition. I t has been found well so t o regulate the supply t h a t water is added t o the bath about half the time. The temperature is then controlled within 0.1 O C., irrespect-. ive of changes in room temperature.
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intervals of half an hour, as it leaves the condenser and as near t o i t as possible.” This method of intermittent sampling is the one usually employed. I t will give a fairly satisfactory sample where entrainment in multiple effects is being studied. However, in the case of vacuum pans, in which the quantity and the viscosity of the boiling material are constantly changing, such a sample may fail t o be representative. The writer has devised a n apparatus by means of which a sample may be taken continuously throughout any convenient period. It has been used successfully for two years. The accompanying print shows the arrangement. “ A ” is the leg pipe of the condenser of the evaporator. “ B ” is a quarter-inch pipe entering the leg pipe near the top. “ C ” is a second quarter-inch pipe entering a t any convenient point below the lowest level a t which the water column in the leg pipe will stand when the evaporator is in use. These quarterinch pipes project into the leg pipe about two inches. This prevents rust and dirt from the sides of the condenser from washing into the sample. ‘ I D ” and “ E ” are heavy glass carboys. They are connected as shown in the small drawing. All connections must be air-tight. I When the valves on “ B ” and “ C ” are opened the sampling apparatus becomes a part of the vacuum system. The condenser water is forced through “ C ” into the carboy “ D ” b y the pressure of the column of water in the leg pipe above ‘IC.” By manipulating the valves the water may be made t o flow into “ D ” in a full stream or drop by drop as desired. “ E ” serves as a trap t o catch any water from the upper pipe when the vacuum is broken.
, B O TDTELTE A ICLO NOFN E C T I O N S . AN
APPARATUS FOR CONTINUOUS SAMPLING OF CONDENSER WATERS FROM EVAPORATORS. B y GEORGEP MEADE
METHOD
Received M a y 16 1911
Mr. R. S. Norris, in his article on “The Determination of Sugar Lost b y Entrainment from Evaporators ” in THIS J O U R N A L , October, 1910, gives the following method of sampling condenser waters. “ Five liters of condenser water are collected, a liter a t a time, a t
&/ N O= 58-14
CONOE N S L R
AT-GRAMERCY
WATER.
REFINERY.
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THE J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y .
The sample will stop running when the vacuum is broken b u t it will start again when the vacuum is sufficient to lift the column of water in the leg pipe above the level of “ C . ” Preparatory to taking a sample the rubber connection between “ C ” and “ D ” should be broken and the end of “ C ” immersed in a little clean water. The valve is then opened. The water will be drawn through the pipe and will clear it of rust and dirty water. The carboys used must be carefully selected. There is danger of a serious accident if they are not sufficiently heavy to withstand the atmospheric pressure. As a precaution they should always be covered with bagging when in connection with the vacuum system.
with glycerin and the determination can be made irrespective of whether the glycerin at the beginning of the operation is above or below the temperature a t which the determination is to be made. This i found to be much better than placing a rubber tube over the capillary glass tube, as is sometimes
B
CUBANAMERICANSCGARCo., NEW YOBRand CUBA.
AN IMPROVED PICNOMETER FOR GLYCERIN, B y L. W. BOSART,JR. Received April 2 7 , 191 1.
The picnometer used is of cylindrical form, with thermometer ground in central neck, and with fusedin capillary tube a t side. The Geissler form with ground-in capillary may also be used if preferred. The cap which fits on the capillary tube as usually provided has no opening at the upper end and it is found expedient t o attach a rubber tube to the lower opening of the cap, and hold the upper end in the small tip of a blast-lamp flame, while blowing through the rubber tube until a very small hole is blown through the glass. By means of this hole, the air can escape when the glycerin expands and enters the cap and will not run down the sides of the capillary tube. After the cap has been placed on the apparatus, the picnometer may stand and be weighed a t any convenient time. The improvement on the usual form of picnometer consists of a small cylindrical shaped funnel, 38 millimeters total length, and I 5 millimeters outside diameter. This is ground to fit the capillary tube. When the glycerin is poured into the picnometer, this funnel is placed on the capillary tube and filled
done, as i t is easier to see if the funnel is perfectly clean. It also allows for greater contraction of the glycerin and gives opportunity for better observations. A cover made from the closed end of a test tube may be placed over the funnel to prevent a n y water being splashed in while the apparatus is in the bath. Funnels of this description are made for us b y Eimer & Amend, to fit the picnometers we had in use. LABORATORYOF THE P R O C T O l A N D GAMBLE Co. MANUFACTURING NEW YORKCITY
ADDRESSES. FACTORY SANITATION AND EFFICIENCY.’ B y C. E.-A. WINSLOW, Associate Professor of Biology, College of the City of New York and Curator of Public Health, American Museum of Natural History, New York.
It may fairly be maintained t h a t in most industries the largest element invested is what may be called life capital. For example, in the cotton industry in 1905 there was invested a capital of 6 1 3 million dollars while the pay-roll amounted to 96 million a year, Capitalized a t 5 per cent., this pay-roll would correspond to an investment of 1920 million dollars in the form of the hands and brains of the workefi. The 1 Presented before the Congress of Technology, Massachusetts Institute of Technology, Boston, April 1 1 , 1911.
July, r g r r
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calculation is perhaps a fanciful one ; but it illustrates the fundamental fact t h a t the human element in industry is of large practical importance. Once the operative is trained and at work it is generally assumed t h a t the results obtained will depend only on his intrinsic qualities of intelligence and skill. The effect of the environment upon him is commonly ignored, b u t its practical importance is very great. In industries where it has been shown t h a t the machine which makes a given fabric requires certain conditions of temperature and moisture for its successful operation these conditions are maintained with exemplary care. In every factory, however,
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