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success even of a n industrial organization, lies in a fuller, freer, more generous publicity of the scientific results of their laboratories.1 Would’that we might benefit b y the experience of Solomon, King of Israel, who, when asked “ W h a t shall I give unto, thee,” replied, “Give me knowledge and wisdom,” and he was answered, “Wisdom and knowledge are granted unto thee; and I will give thee riches and wealth and honor.”
CONTRIBUTION OF CHEXISTRY TO SANITATION.2 B y WILLIAMP. MASON. Received March 1 7 , 1911,
I t must be noted a t the outset that the above title is confessedly too broad for a single paper, so that only a small part of the large field can be here touched upon, leaving the balance to be covered b y others better qualified t o deal with its several portions. Within the memory of most of those present the public took but a slight degree of interest in the hygienic character of drinking water, and while they evinced some concern as to the analyses of supplies for boiler or for laundry purposes, the water intended for table use was judged as to its fitness by its physical properties alone. Although i t is still hard t o convince some people t h a t anything can be wrong with a water which is acceptable t o the senses, yet the wave of education in such matters has extended far and we find a material amount of inquiry as t o the nature of a supply which is offered for public consumption. No one familiar with the way the laity view things chemically needs to be reminded of the existence of a firm belief wide-spread among them t h a t laboratory results alone are quite sufficient foundation whereon t o base a n opinion concerning the suitableness of a water for household purposes. N o chemist has to be told of the fallacy of such a notion, but for the benefit of such of the non-professional public as may be here present, let i t be said that of the three forms of water examination, ‘ I chemical,” “bacteriological ” and “ inspection of the source,” the third is altogether the most important. While none of these procedures should be wanting for the formation of a safe opinion as to purity, yet though it may sound like heresay t o this audience it must be admitted that either of the two laboratory methods taken alone is, in general, inferior in value to a careful “sanitary survey” conduced by one trained in such work. It was said above that within our memories but little interest was shown in the chemical analysis of table waters. As a matter of fact, there was but little in the analysis itself wherein interest could lodge. I very well remember the occasion of my first analysis of t h a t kind. The method of attacking the problem was simplicity itself: Evaporate to dryness for total solids ; ignite t o redness ; restore lost carbon dioxide b y use of ammonium carbonate; gently ignite off excess of the said salt; weigh the inorganic solids, and 1 Dr. 2
Carl Otto Weber in The Chemisfry of India Rubber. Paper read a t the dedication of the Chemists’ Club, March 1 7 . 1911.
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the work was done. Of course bacteriology was n o t yet born, or rather i t was still in its infancy. Fancy the kind of results that could be secured by a method such as the above when comparing a harmless moorland water, high in color, with one drawn from a typhoid infected well. The heavy “ c h a r ” would arouse suspicion in the first instance, and its absence would “pass” the second sample as pure. Following quickly upon such crude procedures came the complete combustion process of Frankland and the albuminoid ammonia method of Wanklyn: the former destined t o make b u t small headway among analysts in this country, and the latter, though modified, to be widely adopted. Bacteriology, although still in the background, was making rapid progress and a little later when it did come to t h e front, it forged ahead of its legitimate position, as did radium, and tuberculin, and 606 and other examples of over exploited discoveries. Those were the days when pronouncements were confidently uttered as to the presence or absence of the bacillus tyghosus in any water sample submitted for examination: the days when chemistry was expected by some t o shortly retire from the sanitary field so far as water work was concerned and when chemists and bacteriologists held very different and very hostile camps when considering the “water” question. I t does not seem so very long ago that the writer was invited to attend a meeting in New York of chemists and bacteriologists, t h e topic of the hour having been which method of examination gave the more correct decision as to the safety of a water for domestic use. Is is to be wondered a t that when the question was finally called for the votes grouped themselves in entire accordance with a prophetic utterance delivered before the meeting began. We have outgrown such discussions now, knowing as we do that neither bacteriology nor chemistry can by itself answer all the questions that may arise, and to-day the water examiner is only too glad to call to his aid the contributions offered b y both sciences. Since the radical changes in methods of analysis inaugurated by Frankland and Wanklyn were first presented the alterations in chemical procedure have been rather of the nature of modifications than the introduction of new processes, or a t least that is true for what may be termed “routine” water analysis. Sundry of these -modifications have been very acceptable, such as the statement of “turbidity” and of “color” in “parts per million” rather than in descriptive words as of old, and also such as the quick methods for detection and determination of the metals. Weston’s method for manganese is a n instance in point, and the use of “ formaldoxime” t o detect copper in solution is another. The.latter is especially useful since the employment of copper sulphate for destruction of algal growths has become so frequent. The examination of water for the presence of t h e heavy metals is certainly more often undertaken than it used to be, and there is a growing feeling that it is wise t o go beyond a simple statement of what metal is actually present in the sample a t the time of analysis
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a n d t o determine what the water in question would do in the way of acting upon the common metals should i t come in contact with them. In other words there often is great value lying in a foreknowledge of just what may be expected should some certain water be sent through pipe of specific character. For that reason i t is the part of wisdom to experimentally test the action of a water upon sundry metals and to state the result as a note to the analytical report. A14hough we know in a general way t h a t softness, acidity, dissolved gases and the presence of much chloride or nitrate will tend towards metallic action, while alkalinity and hardness are rated as protective agents, yet it is far better to actually test a water with reference to its behavior towards metals than to attempt any prophecy of what it will do based upon analytical knowledge of its contents. And me may add that the rate of action of the same water is not only variable, but the ratio of the total action during different lengths of time is not a simple one. Thus, the quantity of metal attacked in ten hours is by no means ten times that acted upon during one hour. In one particular chemistry has shed no recent light upon the subject of water analysis and t h a t is in the matter of testing for chlorine.” Knowing as we do that chlorine forms a part of every pollution from sewage inflow i t would aid us greatly did we have a reliable means of detecting small variations in the quantity of it present. When we recall the great delicacy of some of the other tests in a routine water analysis we are struck by the comparative crudeness of what is available for chlorine. If some really delicate test for it were a t hand then closer estimation of the amount of “cyclic salt” could be had, better maps of “normal chlorine” would result arid a needed revision of the per capita influence of population upon a water-shed would follow. “ Hardness ” determination is another item with which the water analyst is not entirely satisfied, but the necessity for close accuracy is not so important in this case, as is shown when we consider the difficulty of interpretation. The question “ W h a t is a hard w a t e r ? ” is not a n easy one to answer. Of course waters lying near the extremes of “hardness” and “softness” may be readily classified, b u t there is a pretty broad middle zone where doubt begins to appear a n d one is forced t o conclude that personal likes and dislikes enter very largely into the question. After looking into the hardness of many waters on the Atlantic coast, the writer finds t h a t the users of those waters are possessed of great variety of opinion touching the merits of their several supplies: for instance, a hardness of 41.0 parts per million is rated as “ a little hard but good for washing;” a hardness of 31.0 as “good for boilers but not entirely satisfactory for washing;” a hardness of 46.0 as “very good;’‘ another hardness of 46.0 as “ n o t satisfactory;” a hardness of 63.0 as “too hard for boilers or laundry;” a n d a hardness of 7 0 . 0 as “complaint from laundries only.” From a consideration of expressions of opinion such as quoted, the reasonable division would seem to be t o ‘I
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class as “soft” all waters below 50 in hardness, to call “ h a r d ” those t h a t run as high as 100 or more, and to leave the space between these numbers as a.kind of debatable ground wherein individual views shall govern. As with “hardness” so with “iron,” so far as popular opinion is concerned. There are many contradictory statements regarding the amount allowable in public water; thus among the eastern waters above cited as much as 0 . 7 2 Fe per million was allowed to be acceptable, while in another city complaint was entered against 0.3 8. The layman knows from his own experience whether or not a water is producing scale in his boilers or is making red spots on the linen in his laundry, so that the chemical analysis merely furnishes reasons for a knowledge of the facts already in his possession; but he does not know if drainage be entering his drinking water, nor can he find out by inspecting the analytical data. To him the figures on the report sheet are meaningless and he demands an interpretation of them. Such a n interpretation the chemist cannot always correctly give, using his data alone, for he needs the aid of the bacteriologist to supplement his own work and yet he sometimes does by himself what the bacteriologist can never do, namely, foretell future danger in a water which for the time being is not harmful. N o better illustration can be given of the dependence of these two branches of science one upon another than the instance of that well water which, though harmless a t times, became dangerous during periods of wet weather. Chlorine from the contents of a neighboring cesspool was always present in the water of the well, but, except when overtaxed during stormy weathex, the intervening soil presented a n efficient filter against the entrance of intestinal organisms. Thus chemistry a t all times hung out the warning flag while the sister science was powerless, except a t intervals, t o show the danger. Of course illustrations of a reverse condition of affairs can be cited. Take for example a very recent case. Badly polluted water was passing into a city’s conduit line through a leaky “emergency” gate, and chemistry, because of the great dilution, failed to detect this fact; while on the other hand the character of the bacterial contents of the water immediately aroused inquiry and the trouble was located. Many similar citations could be given. Before leaving the topic of interpretation of analyses it is right to add that we cannot but deplore the fact t h a t not a few opinions are still given without sufficient knowledge of the conditions surrounding the source of supply; t h a t is, without “ t h e sanitary survey.” N o t long since the writer had to do with a deep water of most excellent character which a town in the west had been fortunate to strike b y rock boring. A sample of t h a t water was shipped a long distance and examined b y a man who condemned it upon laboratory information alone, t o the very great disadvantage of the people interested. High nitrates and nitrites, or none of these and high ammonia, may readily be found in deep waters; high chlorine
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is common enough and of course a high count of bacteria. must be expected from samples not packed in ice during transportation. Is not the risk of venturing an opinion on laboratory data alone pretty much the same as t h a t assumed b y the physician who formulates a diagnosis and writes a prescription without seeing the patient? Finally, let i t be said t h a t a water analysis is, for purposes of economy, rarely made complete. For ordinary drinking water the question is always asked “ i s i t wholesome?” To answer this, the analysis of the mineral residue left upon evaporation is not usually required, so t h a t much time and expense may be saved b y simply reporting this as “total solids.” On the other hand, analysis of mineral waters deal with this feature of the examination very largely, and usually t o the exclusion of those portions, such as “albuminoid ammonia,” “required oxygen,” etc., which are important in the “ sanitary analysis.” The same may be said of the analysis of waters for boiler use. When we come to protective measures for the general improvement of public waters, chemistry is now doing much more than simply furnishing the clarifying dose of alum: a means of improvement known t o the ancient Egyptians. Copper sulphate, ozone, bleaching powder and the other hypochlorites are among the resources t o which the water purveyor may turn for relief in the event of difficulty. At the time copper sulphate was first proposed as a chemical cure for stopping the plague of taste-producing algae, comment was made regarding the remark of a veteran water engineer who once said: “ N o one who can row a boat should fear trouble from algae.” What the old man meant we now can only guess, b u t i t may have been t h a t he possessed the secret of “coppering” reservoirs and carried his information with him t o the grave. How useful copper sulphate is in curing objectionable plankton tastes is now widely known, nor is the “coppering” of water restricted t o the killing of algae alone. The process is in use for the destruction of bacteria during times of epidemic disease, although, in the opinion of the writer, ordinary bleaching powder is a much more certain agent for such work. Within a few weeks past some 19 pounds of copper sulphate per million gallons of water have been added t o the supply of a western city during a n outbreak of typhoid and the results have not been as beneficial as expected. Without doubt less than half t h a t dose of ordinary “ bleach” would have proved much more satisfactory. Since the introduction of “ bleaching powder” three years ago for the purpose of ridding water of pathogenic organisms the method has grown so in popularity t h a t to-day it is not too much t o say t h a t practically all the new filter plants in course of erection have added t o them devices for the introduction of “bleach, ” should occasion suddenly demand its use. What this chemical will do in the way of killing intestinal organisms is now a matter of common knowledge and i t would seem t o be a n unwarranted assumption of risk t o fail t o provide means for quickly
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supplying i t in event of necessity. In this connection it should be said that “bleach” is especially serviceable under those unfortunate conditions when, because of some accident, the regular water service is cut off and temporary recourse is had t o an inferior ’ supply for the purposes of providing fire protection. “ Emergency” intakes are always sources of danger and many a life has been sacrificed through filling the mains with dilute sewage t o guard against fire losses, as is instanced in the typhoid outbreaks of Butler, Lowell, Toronto and many another town. Judicious use of the hypochlorites during these I ‘ emergency” periods will remove threatened danger and is infinitely better than trusting to a notice t o “boil the water ”-advice which the careless portion of the community will never follow. I t is true that sodium hypochlorite, prepared b y electrifying a common salt solution, may be used in place of the better known “bleaching powder,” but i t requires much more careful attention for its administration and i t probably cannot be furnished a t so small a cost. As a germicide it has no advantage over the “bleach,” but i t is distinctly more in favor with the general public because of its being a product of water, sea-salt and electricity, a combination which is looked upon b y the people as being free from the dreaded ‘ I chemicals.” Ozone is another product for water purification which, on purely aesthetic grounds, is very acceptable to the masses, inasmuch as it is in their minds simply “electrified air.” I t is efficient and will do all that is claimed for it, but can we afford its use? The weak points connected with the use of ozone are: first, its cost; second, the liability of the apparatus t o get out of order. These objections will doubtless be overcome in time and are reported by those interested as being already overcome. But we lack a collection of data upon a large scale. What we need is a municipality willing to take the risk of erecting a large plant operated upon the ozone system. We should all be delighted to study the results, and we should be glad to congratulate such a city in the event of success and to use the information accumulated; but would we be entirely disposed t o share the expenses in the event of failure? On the whole, while we admit the efficiency of ozone and while we look hopefully towards its practical success in the future, we cannot but feel that a t the present moment with the meagre data we now possess we should run considerable risk in recommending its introduction as a means of purifying a municipal water supply. Much as chemistry has had to do with the sundry processes of water “softening,” yet from a sanitary standpoint such procedures are of minor importance because the reduction of hardness is primarily undertaken for industrial reasons rather than for the protection of health. When we consider that as Whipple has shown, “ f o r every increase of one part per million of hardness the cost of soap increased about ten dollars per million gallons of water completely softened” and t h a t a n aqditional drain on the people’s purse must come
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from the disadvantage of using hard water for boilers number of The Engineeritfg News, dealing with the and other industrial purposes, and further, when we proposed law for licensing engineers : note the inclination of sanitarians to put reliance upon “The State proposes to grant a license t o a man t o the claim of English authorities that the drinking of practice civil engineering and to declare under the ofhard water is not closely related to disease production, ficial seal of the State that the man is ‘ properly qualified it is easy to be seen that long before the health authori- to practice civil engineering, ’ which the law defines ties can cry out against the hardness of a proposed to be any branch of the profession of engineering other public supply there will be bitter complaint lodged than military! There is about as much sense in such by the manufacturing portion of the commtmity. a proposition as there would be in declaring under the As has been already intimated, it is exceedingly State’s official seal that a man was properly qualified difficult for the chemist to stand alone when con- to keep a hotel, run a steam shovel, act as cashier of a sidering sanitary problems. His field of inquiry con- bank, fill teeth in a dentist’s office and practice law. “ N o reputable and honest engineer, no matter how tinually overlaps th.ose of other scientific men and he requires their assistance to complete his work. This eminent in the profession, would dream of claiming is especially true in water investigations, wherein, as himself competent and qualified to practice in all has been said, bacteriology becomes so vitally im- branches of the engineering profession.” The engineer’s profession is large and varied. So is portant on both the qualitative and quantitative sides. When a water expert undertakes the solution chemistry and so is sanitary science. No man can of some important water problem he has only begun begin to cover the modern field in any one of these his task when he has secured a chemical analysis of the callings and when in the practice of his profession he supply in question.. He must of necessit.y supple- finds, as he is sure to do, the more or less frequent ment this with a bacteriological examination and it interjection of questions foreign to his specialty, the may be he will also have to call microscopy to his aid only relief possible for him is to seek aid from those in order to settle questions touching the presence of of his fellow scientists who have had experience in local plankton involving a study of the production of such problems as the one a t hand. There is an interdependence of specialists which is constantly growing taste and smell. Of course such matters as the building of reservoirs, more pronounced in view of the ever-widening field of conduit lines and similar structures are relegated a t knowledge, and a part of the equipment of a successonce t o the civil engineer, but some small knowledge ful man lies in his knowing just where t o secure the of the fundamental principles of hydraulics must be kind of aid he needs, where to find the right man t o comprised in the mental equipment of the water join him in the work of a commission, where to get, specialist in order t.hat he may properly deal with the first hand, that collateral accurate information which occasional questions which legitimately fall to him for it would be so tedious and difficult for him to obtain answer. For instance, within six weeks past, while for himself. In view of the existence of what was above termed investigating a serious typhoid epidemic, the writer had occasion to call the attention of the city com- the “interdependence of specialists” is it not patent missioners t o the certainty of foul water reaching that a sort of chemical clearing house is needed and the general supply, should a leak occur in the conduit that a club like this supplies the want? Here men of line laid on the bottom of a sewage-polluted bay. many forms of professional activity are a t home and The commissioners were confident t h a t no inflow here they may exchange their views with mutual could take place in the event of a leak because of their benefit; not always in the form of critical reviews of supposition that the water in the conduit was under formal papers, but often in that more valuable type of pressure, a view which was manifestly in error, for discussion, namely the intimate and friendly chat there was no more possibility of internal pressure than upon topics of common interest. One of the greatest contributions that chemistry there is in the case of a slightly inclined lea,der taking water from a roof. I t would have been unfortunate has made, not only to sanitary science, but to all to have interrupted the investigation until an engineer’s branches of the broad chemical field, is epitomized opinion could have been secured upon so simple a in the erection of this beautiful and most useful building as the central home for the chemists of America. matter. I t is not expected that the water specialist shall draw so largely frcim the science of medicine as to be COMMERCIAL PRODUCTION OF AMMONIA . l able to sit by the bedside and treat a case of typhoid B y c G ’rUFTS. fever, but it is essential that he know something of the longevity of the typhoid organism, be acquainted Received hlarch 3 , 1911 with the conditions under which i t is likely to give The commercial production of ammonia is a fairly trouble and be prepared to rectify them. He touches comprehensive subject. Ammonia has been sought the outer boundaries of those fields of science with in almost every nitrogenous substance and the literwhich his daily work brings,him in contact, but he ature of the industry shows hundreds of patents for does not presume to seriously enter them and when getting ammonia from its native deposits in Tuscany he needs information as to what they contain he ap- and South America and for recovering it from sewage, plies for aid to those who know. 1 Read before the Syracuse Section of the American Chemical Society, Allow me t o quote from a n editorial in. a recent Dec 9. 1910
