AV.,
1914
T H E J O U R N A L O F IiVDL‘STRIAL A N D E N G I N E E R I N G C H E M I S T R Y
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NOTES AND CORRESPONDENCE T H E USE O F OZONE IN VENTILATION1
in spite of the fact that all windows, ventilators, and exits were closed. The management used ozone between the acts and found, It is my purpose to present detailed reports on the present to its satisfaction, that the cases of fainting that had been regular status of ozonization of air for ventilation. The statement of every Sunday disappeared entirely. The influence of ozonized air is especially great upon the respiratory excretions and some persons that the engineering profession would never have thought of using ozone had i t not been for an exaggerated idea odors coming from the mouth and nostrils. These odors are of the physiological benefits of breathing ozone is false, as will prevalent where there is much smoking in a closed room. be proven on regarding the history of the technical development The stale tobacco smell is strongly influenced by the ozone. Professor Rietschel made detailed investigations in this subof the ozone question. ject when the Reichstagshaus (House of Commons) was When the ozonization of drinking water had become widespread, to be equipped with an ozone plant. He recommended the the industries realized “ t h a t the direct breathing of ozonized introduction of ozonized air to the great recreation room in the air in itself was an insignificant fact, while on the other hand the ozone percentage in the air was of great importance, as it certified building, as the original ozonators were not able to introduce t o a certain purity of the atmosphere.” It was thought that the enough ozonized air to do away with the disagreeable restaurant ozone apparatus used for sterilization of drinking water could odors. The result was satisfactory, as is shown by the quotation not be used for ventilation purposes, and the manufacturers set from Director Jungheim, of the Reichstag: “In answer t o your to work and constructed new types. Practical tests were then letter of the 15th of May, 1913, I would say that the ozonator plant in the Reichstag works to complete satisfaction, and that made to show that ozone, even in small percentages, was able to purify the air by removing, or a t least by lessening, bad odors. the smell from the restauramt, as also the disagreeable odor from I would call attention to the experiments by Dr. Liibbert in smoking tobacco, has almost entirely disappeared.” The observation has been made that it takes time before the Hamburg, made in the hold of the steerage of an ocean-going vessel, which experiments marked an epoch in this question. odors disappear. That is because inherent odors are very tenaThis was in 1907 and was reported in Gesundheits Ingenieur. cious in rooms. All materials, however, absorb the ozone odor quickly and readily. The obnoxious odors disappear and give Liibbert’s results were, of course, attacked by various other place to the fresh odor of ozone, which reminds one of freshly scientists, but nevertheless, the fact remains that he succeeded in showing that i t was possible to reduce bad odors by ozone and bleached wash. With a longer use of ozone in moderate strength thus make the air in an enclosed space bearable. The theoretical the action takes longer, but lasts longer, and the ozone will condiscussion in Liibbert’s reports is immaterial; what interests the tinuously eliminate the bad odors, as in the Reichstag, where the engineer is the practical fact that bad odors caused by human restaurant ozone plant is used only for one hour a day. The respiratory and life processes can be influenced by ozone so that same influence was observed in the vaults of banks where the ozone offset the strong smell of newly laid linoleum. I cannot their disagreeable consequences are eliminated. The Congress for Heating and Ventilating in Frankfurt (1910) agree with my colleague when he states that the inherent odors was the first one to spend some time on the question of ventila- must be first driven out of the materials, walls, etc., before they can be effectively eliminated by ozone. I would like to use the tion with ozone. Engineer Cramer gave a synopsis of the work done to that time on the problem. Cramer stated that an word counterabsorption” for this influence of ozone, showing ozonization plant would never be able to take the place of a that the bad odors give way to the odors of ozone. Peculiar and ventilating plant, but it would be able to be an efficient aid in of great importance are the disagreeable mixed odors during the ventilation. Engineers acquainted with both branches of the ,first few days. The belief that these “ mixed odors ” were ozone industry will know t h a t a combination of ventilating and ozoni- has often led to mistakes which have played an important role in judging the value of ozone for ventilation. IVhere there are zation plant does not lead to a curtailing of the ventilating plant, numerous odors found in new buildings i t is advisable to let the but i t is clear that such places as the vaults of banks, public baths, and industrial plants would he able to eliminate the too ozone apparatus work a few hours before and after working hours, when nobody is in the buildings. If this is done it will not be frequent changes of air if they were to combine their ventilating necessary to use the ozone plant during working hours until the plant with an ozonization plant. Experience shows that ozone ventilation has two very im- mixed odors have been eliminated. I have numerous opinions portant points which recommend its use everywhere. These from private people who have been in a position to observe ozone plants for years and who know their working from A to 2 . I n are: first, the i i a j u e n c e o n odors; second, the p u r e l y physiological e f e c l s . This report is merely to corer actual experiences and these reports you will hear from physicians who state that the is not to discuss theoretical questions. There will be no discus- influence of ozone has almost entirely eliminated the odors of sion as to whether ozone merely covers up odors, or oxidizes sickrooms ; you will hear from abattoir managers and veterithem, The personal ideas of the author were laid down in GPS. narians, who say t h a t the bad air in the dispensaries and a h t I n g . , 1913,No. 16, in an article entitled “Improving the ilir in toirs h a r e been improved; you will hear from bank directors, Baths by Means of Ozone.” The fact remains that the intro- who bear witness to the excellent influence of ozone on thc air duction of ozonized air in a room filled with stuffy air brings re- in their safe deposit vaults. Architect Bielenberg, who has had much occasion to notice the lief, not only to the people in the room but to others when they enter the room. This is especially clear when a person enters a influence of ozone on room air, says: “ A propcrly installed crowded room from the outside before and after the use of the and well regulated ozone plant, according to my opinion, adds ozonized air. After a few minutes there is a marked difference much to the improvement of the air; i t improves the general state of health of the people in the rooms and increases the in the atmosphere in the room, which is plainly discernible. Years ago experiments were made in a Berlin theatre on a Sunday working capacity of the individual.” The question of how much influence the weakly ozonized air afternoon, when the theatre was crowded, and i t was possible to create a pleasant atmosphere in the theatre within 40 minutes, used for ventilation purposes has on the bacteria in the air is of little importance a t the present time. Kevertheless, we cannot Address by Ludwig von Kupffer. of Berlin, a t the 9 t h Congress for dismiss the question, for it is here that the contrast bet\wen Heating and Ventilating. Cologne, Germany. June, 1913. Abstracted b y Dr. M. W.Franklin from Gesundheits Ingenieur, Aug. 16, 1913, pp. 605-615. theory and practice seems to be the strongest, for in regard to n y LEDWIG V O X KCPFFER,of B ~ R L I K
‘ I
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T H E JOURNAL OF INDUSTRIAL A N D ENGINEERING CHEMISTRY
air purification or air improvement we find the greatest difference in opinion as regards the question whether ozone is really able to purify the air, or whether i t only covers up the odors; whether, therefore, ozone ventilation is effective or not. Scientific investigations have shown that ozone has no influence on dry bacteria and on the other hand actual practice furnishes us with proofs that even very weakly ozonized air is able to retard the growth of bacteria of putrefaction and of fungus growths. Here we have a n antithesis between laboratory results and practical results. Ozonized air is very important in the ventilation of abattoirs and cold storage plants and its adoption in many of these plants is for the very reason that it retards the growth of bacteria, a fact which sanitary engineers grant. We have on the one side the results of Ohlmiiller, showing that ozone cannot kill dry bacteria, and on the other hand, practical results show that ozonized air has a retarding influence on their growth. We can explain this contradiction only by some indirect influence, perhaps due to some oxidizing or chemical process acting upon the soil on which these bacteria grow. This chemical change in the soil would be equivalent t o a withdrawal of food supply, through which both the growth and the power of reproduction of the bacteria are retarded. This problem has some interest, for if we'are able to prevent the growth of germs, or in other words, prevent the formation of soil for their growth by means of ozonized air, we should do so. I can speak briefly on the question of the poisonous nature of ozone and its supposed harmful effect. Prof. Czaplewski' has given detailed information on this point. The practical engineer knows and knew years ago, when there was no question as regards the poisonous nature of ozone, that too large quantities of ozone are harmful. However, even heavily concentrated ozonized air is bearable, though, with difficulty, and has no influence on health. There are men here in this congress who have been in contact with heavily concentrated ozonized air without having suffered in their health. Moreover, Dr. Erlwein shows t h a t the laboratory tests showing the harmful nature of ozone were made with concentrations which were zoo to 1000 times as great as those used for ventilating purposes. The report of Prof. Czaplewski shows that we must differentiate carefully between highly concentrated and weakly concentrated ozonized air. For ventilating purposes the weakly concentrated ozonized air alone need be considered. The limit of concentration in practice is 0.3 mg. per cbm. For pure ventilating plants we rarely use concentrations above 0.09 mg. That these weak concentrations t h a t are hardly perceptible to the senses are still beneficent for ventilating purposes is an assured fact brought out by practical tests. The oft-occurring statement that ozone can not have a destructive effect on impurities in the air, when used in such small quantities, does not seem to have been proved even by the numerous exact tests. We h a r e to deal, as Prof. Czaplewski says, with very different excretions; some known, some unknown, some complex, others easily volatilized. The tests with only known odors seem in most cases t o show a direct influence of ozone. These tests (hydrogen sulfide, skatole, indole, merkaptane) were made with quantities which could be measured. Consequently, we have a very important use of ozone. It is probably immaterial, as far as the effect is concerned, whether measurable quantities, like 0.1 g. ozone and 0.001 g. skatole; or 0.1 mg. ozone and 0.001 mg. skatole, which latter can not be accurately measured, react on each other. It is well known t h a t many odors, which quantitatively can not be found in the air, have a n effect on our senses and are obnoxious. I think i t therefore extremely probable that small quantities of ozone have a beneficial effect on these small quantities of obnoxious odors, especially when it is a question of those very volatile and, chemically, partly unknown odors. Only in this way can we reconcile I
See M e t . C h e m . E n s . , 12 (19141, No. 4.
1-01. 6 , S o 4
the statement made by Prof. Bail, of Prague, and of Prof. Goltz, of Berlin, t h a t putrefaction odors and fecal odors are reduced with even small quantities of ozonized air acting upon them, while others claim that ozone could influence these odors only in abnormally large quantities. Ozone concentrations ahovc I mg. per I cbm. do not come into consideration in practice. hTomatter how interesting may be the tests made with animals, they have no importance for the ventilating engineer. The ozone industry agrees with Prof. Czaplewski that in ozone ventilation ozone should be used that is entirely free of nitrogen. Konrich used a so-called lattice (grate) apparatus xhich was only cooled by the air passing through it. The electrode grate acts often as a dust catcher; the very fine dust particles gradually burn, whereby nitrogenous gases may form in small quantities. How far Konrich took account of these points is not known. It is my opinion that my colleague overestimates the danger of the nitrogenous gases in the use of ozone; the small quantities of these gases which an ozone apparatus forms are in no relation to the quantities formed by a single arc lamp per hour and are of course infinitely small related to the total quantities of fresh air in the rooms. With tests on such a small scale as made by Konrich, the relation between air, ozone and nitrogen gases no doubt might be significant. In practice we follow these points : Weak concentration, good regulation and minute distribution are fundamental requirements for a safe but also an efficient plant. In order t o prevent the formation of nitrous acid the plant should be kept clean. Attention should be paid to the formation of mixed odors, especially in new buildings, as was mentioned before. The duration of operation will depend on the different conditions. There should never be use of the ozonator plant without accompanying use of the ventilating plant, otherwise the ratio of mixing will be changed and the effect changed. The usual concentration of ozone in practical operation is not measurable with even the best measuring instruments without slight errors. h-evertheless, the strength of concentration, which is the product of the ventilator. capacity and the ozonator capacity, is easily determined. As it is my intention t o report on the practical results obtained in actual practice, I have obtained testimonials reaching over a long period of time. The ozonators in these different plants are made by various firms, whose names are of course not mentioned. The letters here given show that the ozonators have met with success in operation. DEODORIZATION BY MEANS O F OZONE
Hamburg, M a y 31, 1913 Building Department, Section 1 , D e p t . of Street Cleaning and Refuse Disposal T h e employ,ees sheds a t t h e two refuse incineration plants a t t h e Alte Teichweg a n d at t h e Bullerdeich have been equipped with ozone plants. These sheds consist of a locker room, provided for the dirty and filthy clothes, a n d one f o r t h e clean clothing. Both rooms are connected by shower baths and t u b baths. T h e clothes are hung up in these rooms by means of special suspended cords a t such a height t h a t they cannot be reached f r o m below. T h e rooms are ventilated from t h e ceiling a n d heated b y pipes running along the roof. T h e room for t h e dirty clothes is also provided with pure ozone through pipes running parallel a t t h e height of the clothing., , , , . , , , . , T h e blower passes t h e air into these tubes. T h e ozone plant is started up about one hour before change of shifts and remains in operation until two hours after change. Measurements as regards t h e q u a n t i t y of ozonized air per time unit, t h e ozone percentage of t h e air, or t h e ozone percentage of the air between t h e clothes have not been made as yet. About 1 1 2 hour a f t e r starting up the plant the typical ozone smell is perceptible. THE USUAL ODOR O F PERSPIRATIOZ A K D DECAYED R E F U S E COMING FROM T H E S E CLOTHES H A S B E E N SUCCESSFCLLY ELIhlIXATED B Y T H E OZOKATOR P L A N T .
M a y 6 , 1913 Municipal h l a r k e t Management, Hamburg T h e ozonization plant finds geneval approval. Our municipal market is a veritable hothouse. The walls are made of glass and iron and the roof is zinc covered. In summer there is usually a n unbearable heat, and with large crowds, especially on Saturdays, the air was very b a d , due chiefly to the presence of so many people and t h e great quantities of perishable products, m a n y of t h e m of strong smells. T h i s has been eliminated enliuely.
T H E J O U R N A L OF I N D U S T R I A L A N D ENGINEERING C H E M I S T R Y Of course, I have t h e ozone apparatus work d a y and night uninterruptedly in t h e summer, at least during t h e hottest time. T h e ozone smell has, however, not shown a t all or else only t o a very minute extent. WITH CEASING T H E OPERATION OF T H E OZOKATOR P L A S T T H E R E OCCURS VERY SOON A DISTINCT VITIATION OF T H E A I R . T h e public also pays its compliments t o t h e plant, so t h a t I believe I am on t h e right track when I say t h a t t h e ozone plant is a necessary adjunct for municipal markets and similar great public halls. (Signed) vox GLADIS(Manager)
Hamburg, April 6 , 1913 Carl Lippmann C Co. We have had a n ozone ventilation installation for about two years and can say t h a t t h e same works without a hitch in our business, which is connected with KATHER STRONG ODORS, a n d has proved t o be a n absolute necessity. Berlin, M a y 24, 1913 T h e Management of the Municipal Abattoir and Shambles T h e ozonator plant installed in M a y , 1911, for t h e abattoir has proved t o be a success. Even though i t is not possible t o obtain a complete deodorization of t h e air in t h e building in which t h e entrails are reduced, due t o t h e nature of t h e work itself, nevertheless, t h e ozonator plant has resulted in a C O N S I D E R A B L E REDUCTIOS O F T H E S E SOXIOUS ODORS. Harmful influences on t h e health of the employees, due t o t h e ozone, have not been noticed in t h e plant. (Signed) GOLTZ
Complaints by the neighborhood to the odors from this plant have stopped since the plant was installed in 191 I . OZONE APPARATUS IN INDUSTRIAL PLANTS June 6, 1913 Emil Gminder, Reutlingen M y firm, Ulrich Gminder, has had several ozone plants in operation for a number of years. In the cotton spinning and weaving mills where are always found a large number of people and where some of t h e materials give forth a peculiar odor, there has always been very poor air. T h e air is bad with ordinary ventilation, WHILE WITH OZOSIZATION OF THE AIR WE F I N D T H E A I R TO B E PLEAsAKT. Similar plants have been installed with the same success in the big dressing rooms, the offices and other parts of the plants. T h e effect of t h e ozone is felt t o be especially beneficial in t h a t p a r t of t h e mill where t h e fibres in t h e web are singed off by means of the gas flame. During t h e years t h a t I haye been able t o s t u d y our ozone plant I have reached t h e conclusion t h a t ozonization of air is advantageous for all rooms, as long as it is not used t o excess, i. e . , t h a t t h e ozone is either not at all noticed or only very slightly. (Signed) E M I L GMINDER June 7, 1913 Rudolf Rleidinger, Reichenbach T h e ozonization of the air on t h e whole is felt t o be pleasant. T h e heavy, sultry air gives place t o refreshing air. This I have been able t o notice only within t h e last few weeks, when t h e ozone plant was n o t in operation, due t o t h e breakdown of one of the motors. T h e textile industry working t h e cotton is forced t o humidify t h e air, consequently t h e work rooms are liable t o have a warm, heavy, almost tropical atmosphere, in spite of good ventilation. T h e capacity for work suffers of course greatly under this. I was therefore very much gratified last week when the ozone apparatus resumed work again. Breathing and respiring, as also t h e life processes, seem t o go o n much easier in ozonized air, so t h a t one does n o t feel OF THE t h e disagreeableness of t h e hot air. WITH THE ISTRODUCTIOS OZOXIZED AIR I T W A S MORE A P P A R E N T EACH DAY HOW T H E DISAGREEABLE ODORS DISAPPEARED. Today there is no trace of these odors. One of t h e sheds had always had fungi-like growths on the ceiling. These have disappeared since t h e use of ozonized air, after frequent unsuccessful a t t e m p t s had been made previously t o remove these growths by means of copper sulfate and calcimining. There always used t o be a number of workmen who were constantly troubled with diseases of t h e respiratory organs. These diseases have been reduced. While they used t o form t h e majority of all those on t h e sicklist, they are now t h e minority of causes given by the sick people. (Signed) R . MRIDINGER
M a y 24, 1913 Municipal, Gas, Water. Electric Works, Heidelberg I n answer t o your question of t h e 16th inst., I would say t h a t t h e ozonization plant installed in t h e local public baths has proved successful. It was a question here t o remove t h e bath odor usually found in baths. T h e ozone was t o be a deodorizer in t h e first place. Great care must be taken in regulating the percentage of ozone. At first too much ozone was admitted a n d t h e bathers complained a b o u t headaches due t o t h e smell of ozone. T h e ozone percentage was then reduced and worked satisfactorily. T h e ozone odor should not prevail. (Signed) KUEWCK(Director)
335
REPORTS O F PHYSICIANS IN HOSPITALS June 6, 1913 Royal Sanatorium, Winnental Answering your question of the 4th inst., I will gladly assert t h a t w e are well satisfied with success of t h e ozonator plant installed in one of the wards. There are n o scientific facts as t o their influence on the properties of the air. From practical observations, however. we can s t a t e t h a t there have been no disagreeable influences, t h a t the insane have never noticed t h e smell of ozone, A N D THAT IN THOSE WARDS WHERE THERE WERE IXSAXE PATIEEj’TS GIVEN TO UNCLEAN HABITS, T H E AIR H A S BECOME CLE.421ER
AKD
T h e effect was especially gratifying when t h e outside temperatures were either very high or very low, as i t obviated ventilation by means of opening of windows and exposing t h e patients t o sudden draughts. (Signed) D R . KRECSER P U R E R THAK B E F O R E .
Karl-Olga Hospital, S t u t t g a r t June 13. 1913 T h e ozone ventilation plant has been in operation for three years and gives complete satisfaction. It has a strong, deodorizing effect on the wards in t h e hospital. THISW A S SPECIALLY APPARENT WHEN THE PLAST HAD TO STOP FOR S E V E R A L W E E K S TO MAKE SOME N E E D E D REPAIRS. During this time there was much trouble due t o bad odors in t h e wards. No harmful effect from ozone was noticed, either in patients or in attendants. (Signed) DR. V. HOFXEISTER Municipal Katherine Hospital, S t u t t g a r t June 11, 1913 Answering your question in regard t o our ozone apparatus, I can say this: We use a portable plant which we use in places where t h e natural ventilation is ineffective, or else in rooms where there have been patients For the latter purpose with diseases t h a t left a bad odor behind them. especially, t h e ozonator proved t o be excellent. I was unable, however, t o s t a t e t h a t the same had a favorable influence on disease processes, combined with putrefactive processes, especially in t h e lungs, due to t h e breathing of air containing ozone. THE PATIENTS WHO WERE FORCED TO LIE N E A R PATIENTS WHOSE DISEASES BROUGHT WITH THEM ODOROUS DISCHARGES HAVE ALWAYS ADMITTED
THAT THEY
W E R E VERY
GRATEFUL FOR T H E EFFECTS
PRODUCED B Y T H E OZONATOR.
(Signed)
DR.
SICK
S t u t t g a r t Royal Theatre June, 1913 I have mentioned my ideas as t o t h e value of the ozonators some years ago a n d still adhere t o t h e same opinions, which are strengthened by facts found by long operation of these ozone plants. With t h e exception of t h e vacations, t h e ozonators in t h e theatre work every day. THEREIS K O DOUBT THAT T H E OZONATOR I S A GREAT B E N E F I T TO T H E THEATRE P U B L I C .
It also reduces the dust. I have made experiments in dressing rooms and toilet rooms, and have found the same t o be the case. As regards harmful influences due t o breathing the ozone, i t seems t o me t h a t only gross abuse of the apparatus can have such a n effect. (Signed) DR. GUSSMASN OZONE I S ROOMS AND BUILDINGS UNDER NORMAL CONDITIONS Deutsche Bank, H a m b u r g M a y 30, 1913 Those of our employees who notice t h e presence of the ozone s t a t e t h a t the air has been improved and t h a t i t is not as close and stagnated as previously. T h e y say they feel refreshed a n d improved. T h e same s t a t e also t h a t they miss t h e ozone if it is not distributed properly by the great ventilating shaft system used there. They say also t h a t at times they have felt unpleasant, when t h e ozone percentage was too high. Dresden Bank, Hamburg M a y 28, 1913 T h e ozone plant installed here works t o complete satisfaction and the complaints made in t h e past by employees in regard t o poor air have stopped since t h e operation of t h e plant.
There follow a few reports from cold storage plants, which bear on the matter of meat and food preservation. Director Klapp, of the Potsdam abattoir, one of the experts on ozone apparatus, writes: T h e ozone plant has been in operation in the abattoir for three years. During this time there has been no interruption in service nor any facts t h a t might lead t o t h e conclusion t h a t t h e ozone has a bad influence on t h e employees working in t h e plant. OK THE CONTRARY, THE EMPLOYEES ALL LAUD THE BENEFICIAL EFFECTS OF THE OZONE PLANT. T h e f a c t t h a t t h e butchers’ union has recommended the introduction of ozone plants in all abattoirs seems t o be a n excellent indicator of the feeling of the employees in this regard. Aside from t h e report made a t t h e last congress on t h e bacteria contents in t h e air and t h e excellent preservation of the beef, we have t h e tests made last year as regards length of preservation of meats. (Follows a longer report not quoted.)
Director Geiss, of the Straubing abattoir, says as follows: As far as I am concerned, I may say t h a t t h e ozone plant, which has been working since 1911, is in excellent condition and satisfactory in every
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respect. With the aid of t h e ozonators we were able, last fall, t o pres e r \ e beef f o r 55 days without a n y decay in t h e meat. Any odors t h a t occur are removed within five t o ten minutes b y t h e ozonator. Such odors appear a f t e r holidays, as the ozonators are used only a very short time on t h e holidays proper.
Unfortunately, time does not permit me to exhaust this almost inexhaustible field. You may draw your conclusions from what I said. One thing you must admit and conclude, namely: t h a t the ozone industry is not bringing a new apparatus on the market in a thoughtless way, bent only on its own profits. Rather we have found t h a t the ozone industry, in view of the practical results obtained and the many inquiries, was justified in following up this line of experiments and in carrying on and exploiting, a process which seemed good and useful to industry. The ozone industry, moreover, will be able t o adhere to this viewpoint without fear and doubt. OPERATIONS OF STEEL MILLS IN MARCH During March, the steel mills throughout the country continued to operate a t an average rate of about 75 per cent of capacity, although the rate in the Pittsburgh district was estimated a t about 80 per cent. Pig iron production was a t a rate slightly above 26,000,000 tons a year. New business came in a t a very low rate during the first fortnight of the month; this was attributed t o the weather conditions, but there was disappointment that the lull which naturally followed the January buying movement, and which was more or less expected, had not yielded t o more active market conditions by the middle of the month. The sheet mills are now operating a t a n average of about 85 per cent of capacity, while the tin plate mills are operating substantially full. In wire products and tubular goods the conditions are nearly as good. W. A. HAMOR
A RAPID METHOD FOR CASEIN I N MILK-CORRECTION In THIS JOURNAL, 6, 131, the following paragraph should have been inserted a t the end of the article under the above title: “Since the above work was completed it has been found that beechwood creosote serves as an admirable preservative for milk. When added in the proportion of 5 cc. to I pint of milk, the latter keeps in good condition for several months if placed in the dark. The preservative does not interfere with the casein test, nor with the Babcock fat test, provided only onehalf the usual amount of sulfuric acid is used.” W. 0 . WALKER G O R D O X HALL OR C H E M I S T R Y SCHOOL O F h I l S I K G .
KISGSTON,O X T A R 1 0
Vol. 6 . N o . 4
AMERICAN ALCOHOL INSOLUBLE TEST FOR SHELLACNOTE I n the method we have described for the determination of the alcohol insoluble matter in lac, the following statement occurs: “During the extraction the alcohol is kept boiling briskly. The extraction is stopped one hour after the alcohol in the siphon tube has become colorless” [THISJOURNAL, 5 (1913), 4351. We believe it advisable to further standardize the method a t this point and recommend t h a t the rate and time of extraction be kept under precise control. The rate of extraction may be controlled by the use of an electric stove of the Simplex type, 4l/2 inches in diameter, and using the full current of 2.2 amperes a t I I O volts. The volume of methyl alcohol in the flask should be 125 cc. This is in addition to the alcohol required to fill the siphon. The flask should be protected from draughts. Under these conditions the tube will siphon over about 33 times an hour. The condenser should be able to return all the alcohol volatilized during the vigorous boiling of the flask contents, the object being to effect the maximum extraction during the fixed time. The color is removed by the end of the first hour in practically every case and in order to eliminate any variations due to differences of opinion as t o the exact time when the color has disappeared we recommend that the total extraction period be limited t o exactly two hours, time being taken from the moment when the first siphon tube of alcohol has passed over. The methyl alcohol used in this method should be 99.5 per cent, by volume.
Signed: C. T. BRAGG,Cheirman, Director of Laboratories, Berry Bros., Detroit. GEORGEE. ASHBY,of John R. Anderson & Co., N’ew York. A. C. LANGMUIR, Works Manager, Marx & Rawolle, New York.
PARKER C. MCILHINEY,Consulting Chemist, New York. UT.PAISLEY,Chemist, Rogers & Pyatt, h’ew York.
JOHN
Approved: H. S. CHATFIELD, Secretary, United States Shellac Importers’ Association.
PERSONAL NOTES The Russian minister of public instruction has made a grant of $50,000 to the St. Petersburg Academy of Sciences to assist a search for radio-active minerals throughout the Russian Empire. Dr. A I . G. Donk, of the Bureau of Chemistry, has be,en detailed by the Department of Agriculture to cooperate with the Department of Forestry a t the Univ. of Idaho in investigations looking to better methods of utilizing mill waste and refining by-products obtained from stumps. The work will be a continuation and extension of experiments carried on for the past three years by Dr. C. H. Shattuck, head of the Department of Forestry a t Moscow. A Better Industrial Relation Exhibit will be held April 18-25th, a t z West 64th Street, New York City. It will show the devices in modern business which tend to make more harmonious the relations between employer and employee, and t o better the conditions of employment. The Business Men’s Group of the Society for Ethical Culture has charge of the Exhibit, which will appeal to both employer and employee in the manufacturing trades. There will be special evening lectures by industrial leaders of the country.
The American Electrochemical Society will hold its Spring Sleeting in New York City, April 16-18th. The program consists of a Symposium on “Power for Electrochemical Purposes” and papers on “Hydro-electrometallurgical Process.” The American Electro-Platers’ Society will take part in the discussion of the papers on the latter subject. The Franklin Institute of the State of Pennsylvania has awarded its Elliott Cresson Gold Medal to Prof. Wolfgang Gaede for his molecular air pump, in consideration of the very great value of this invention for the quick production of vacua beyond those hitherto obtainable. The Board of Regents of the Vniversity of Wisconsin has created a n Engineering Experiment Station to be established in the College of Engineering and to have general charge of the testing and research work of the college. The staff will consist of the Dean as Director, the members of the instructional staff in the various departments of the College of Engineering and those fellows, scholars and assistants engaged in experimental and research work. This action transfers the appropriation for research now made for the College of Engineering t o the En-
