PSYCHOLOGY is the science of human nature, Commercial advertising is the art of influencing human nature to buy certain wares, Advertisers are discovering that they need to know the facts which psychology can give about what attracts attention, what sticks in memory, what gives a pleasant impression, what persuades and what leads to a given act, here the act of purchase, Psychologists are learning that the responses of men and women to the illustrations and copy of ads are material for the scientific students pure curiosity about the workings of the mind as well as for the economist 01 expert in business. So a new specialization of applied psychology is fairly started, its birthday being perhaps that of the publication of Prof. Scotts Psychology of Advertising in 902. No matter which of the many problems that confront advertising practice you choose, you are soon led straight into psychology-often psychology of a very technical sort-if you try to think the problem through to the end. To make known a breakfast food or soap, to connect its name or appearance or both with the fact that it a breakfast- food or soap may seem an easy problem for common sense. Ruftons Soap ill big enough type, on enough pages, fences, and cards-the method of our childhood-is indeed straightforward and easily done. But common sense does not inform one whether so emblazoning Rutton's Soap on an eighth of a page eight times or on a whole page once, on a page alone or an a page witb a picture, mare surely captures attention and holds memory prisoner, I daes nat even distinguish behveen getting the human mind to think af “saap” when it happens to think af “Rufton's” and to think of “Ruftan's” when it happens to think 01 “saap,” Yet this difference may mean thausands of dallars. Putting Facts Before the Mind. Com man sense has indeed aften made great blunders, neglecting clearness, pleasurableness and habit as causes of attention and aver-emphasizing size and repetition, the castliest ways af catching the eye and mind. Even to-day the elementary laws of attention taught ta beginners in psycholagy are not always followed. }or example, no psychologist amang my readers will daubt that Fig, 1 burns in its message, the ALec Fig. 1. -A strong claim on attention at small cost. Fig. 2.-A weak appeal. Too elaborate, vague, and confused. name of an autamobile, better than Fig. 2, and in a fraction of the space. But the problem of putting a fact, or, mare cammonly, two facts in cannectian, inta a mind, leads soan ta far mare subtle and technical matters. I choose anly one for illustratian-the laws af the actian of the eye, which is the first enemy for an advertisement to win over. The eye, in getting its impressian of a page, a wall, or a billboard, acts roughly as would a small camera, in getting a series of pictures which, pasted tagether, wauld make a picture of the total page, wall or billboard. That is, the eye does not see clearly much at ane time. nar move in a cantinuous sweep to cover the abject. It turns, stops far one to three tenths af a secand, takes in an “eyeful,” turns ahead or back, stops as befare, tal,8s in anather “eyeful.” and sa on. Getting an Eyeful of Advertising. Means have been faund ta phatograph the movements of the eyes in reading a page, examining a picture and the like, and measurements have been made af just how much the eye and understanding do take in during one stap-one exposure af the camera. The reader wha is conscious only of laaking at an advertising page in a magazine for twa secands and getting a view of it as a whale, really takes a dozen ar sa different “looks.” The eye itself can nat see the whale page at all oiearly in one laok or fixation. The eye sends up a piece-meal report which has ta be put together. The task af the eye in glancing aver a page is a campI ex task which may be done well ar ill, easily or with a feeling af strain. The advertiser should, af course, ather things being equal, (1 ) make the labor af the eye as slight as passible, (2) furnish any material that the eye is ta take in at ane glance ar fixatian in the shape af a eonvenient “eyeful,” and (3) arrange the “eyefuls” that are ta catch the eye in its series af exposures in such a way that the piecemeal rep art they give will be mast sure to be put tagether inta the impressian he desires to leave, To meet these requirements even the expert advertiser needs special knawledge of the psychology or visual perceptian. Comman errors are to make type too large, as in Fig. 3, so that a single fixation fails to give any whole phrase ar word, ar ta so crowd and muddle printed matter that the eye moves about the page at random. Less commanly the eye is actually tempted away from the essential facts in the display. Ta get attentian to an advertisement is only a first step in a long pursuit of the mind, which must be at last forced by the laws of its awn nature to write far and read a catalogue, to examine an article, 01, mast cammanly of all, ta buy it, Intuitive Knowledge Supplemented by Psychology. Experienced advertisers who have studied the results of man y a d v e rtising campaigns get an intuitive appreciation of haw men and women will be influenced by this, that and the other quality in an advertisement. Can such intuitions be mefully supplemented by the psychalagist's knowledge af the laws af attentian, perceptian, memory, suggestian, babit, inference and the like? Let us ask, as a sample case, whether advertisers have anything ta learn fram one of the simplest of all psychalogical laws, a law of habit ar conn{ction formation, whieh states tha.t a human being will, other things being equal, make to any situation that response which has gone with that situation most frequentls, and with the mast resulting satisfaction. Man thinks or feels ar does what he has thaught ar felt ar acted in like case with success, Will it profit an advertiser ta think of the possible buyer as a mechanism that, whatever else it does, tends unreasaningly to keep :ogether ideas that have came together? This law leads ta fve obviaus principles far contrailing a person's mental cannections. 1. Knaw what his situatian is. 2. Knaw what response you wish to get from him. 3. Knaw what satisfies 01 an nays him. 4. Make the cannection; do nat expect the rpsponse to came as a miraele. 5. Other things being equal, make no connectiolls which yau will later have ta unmake. That these principles, which should be the A, B, C af any art af influencing human nature, are nat thoroughly knawn ta advertisers, is clear fram the following facts: Advertisements almast exclusively to arrest the attention af a casual observer (e, g., adver-tiseme,nts consisting of an interesting but largely irrelevant picture with a mere nate. of the article and frm name) are used for articles like seeds, doorknabs, nursery stock, ar coffins. This is wasteJul since passible buyers of such wares would in a great majority of cases make a deliberate examination af advertisements af them, the situation including much interest on their part and a definite intention of comparing merits. Advertisers who use expensive attention-arresting display far such articles do not consider '/Chat the possible buyer's situation is. Looking cas- Septe:nber 16, 1911 SCIENTIFIC AMERICAN 2.1 ually over a magazine, looking to :nd where to biY a given article, and looking to find out which is the best article, are three radically different situations that obviously demand different treatment. Getting the Right Kind of a Response. Some advertisements are fitted to produce the response “readiness or desire to buy a motorboat, a piano, a greenhouse” as much as or more than the response “readiness or desire to buy the Jones motor-boat, the Smith piano or the Brown greenhouse:' The response whieh any cOlllpetitor equally desires is COIfused with the respons which the advertiser himself should seek. Certain features of many advertisements of automobiles, Portland cement, bathroom fittings and office furniture make this error. In some such cases a real profit-sharing Of supposed competitors may be the reason, but even in such a case it is wasteful to encourage a response as beneficial to future competitors in the same trade as to the advertiser. Neglect of the third rule, “Know what satisfies or annoys the prospective buyer in the case in question,” is very common. Does not Fig. 4, for example, show a misapprehension of what the possible buyer of a pieno wants? The pictures of the factories and office building seem psychologically fitted to appeal to a man to place a mortgage or perhaps invest in the company's stock, but not to appeal to the desires and aversions of a music-lover in respect to a piano. Are the pictures of the man and the hall-mat borders likely to connect the idea Of a pure, rich tone and of beautiful music with that particular piano? Would not the general rake-up—the arrangement of cuts and type— positively irritate anyone of an artistic temperament? The fourth rule—to make connections, not expect them to come of themselves—seems at first thought childish. But did the “Sunny Jim” “ads” connect a given breakfast food inevitably with ideas of deleetability, health and vigor, s ,ffuse the very name of that food with a charm for appetite, and bind to the sight of its package a strong impulsion toward purchase? On the contrary, I venture to predict that many of my readers who remember Sunny Jim do not even remember what breakfast food was S'!'1posed to have made him sunny; and that many others have, as a result of the “ads,” the hardly more valuable connection of thinking of the food in question as the subject of a vigorous advertising campaign in connection with pictures and jingles [bout a rather ridiculous looking little old gentleman. Making the Connection. As a matter of fact. the greatest amount of psycholog'cal ingenuity is demanded to “ma1,e the eonnection,” simple though it sounds. To connect the article and the name, to connect each desirable quality with the name, to connect that name with the ideas of pmchase and possession--each may be a most intricate task, involving. like a problem in chess, the interrelations of dozens of fadors. Disturb one adjective, leave one preparatory advertisement ineffective, overdo one element in the pict)lre and the who1 attack ma.v faiL I have willfully chosen samples of inadequacy froIn the best mOlleI'l advertising practice, in order to make the point that violation of the psychological laws of closeness, relevance and concreteness are perilous to even the most expert writer of advertisements. For perfectly clear cases one may take th'0se given by Prof. Scoit of the picture of a breakfast food carton with vermin crawling over it, and of the underwear company which received many orders as a result of a second company's advertisement, the second company's “copy” having been so placed as to connect more readily with the first company's name and address than with its own' The last warning, against making connections only 10 have to break them later, should protect any advertiser from many risks. :01 example, the emblem. slogan or means of attracting attention to the “copy” should not risk boring or disgusting readers in the long run for the sake of an exciting appeal for the time being. A history of advertising would, I am sure, prove that the grotesque, the merely strange, and the fantastic have been tbus danger'0us. A psychologist would prefer not to risk bis fortunes on the habits formed by repeated impreSSions of Come Packt furniture, U-All-No after-dinner mint, Slide Well collars, Breathe-rite braces. Corn Dodger shoes, Holeproof hosiery, Pre-Shrunk garments. Yet these are all modern devices used to gain the trade of critical people. The psychologist expects Fig. 5B to outlive Fig. 5A as a catch-Sign, and predicts that even the ('.harming chicken of Fig. 6, that “hasn't scratched yet,” may in the long run bore the public and have to give up his place to the safer picture of the soap itself. I have so far illustrated the value of knowledge of one sample law of human nature—a law of habit— by showing the bad effects of its neglect. On the positive side, I should claim that many of the excellencies of Fig. 7 could have been planned and can be accounted for by the psychological principles of association or connection-forming. Finally, I have chosen two “ads,” Fig. 8A and 8B, which superficially seem much alike, but O:e of which I regard as very good and the other as very bad on purely psychological grounds. Let the reader decide which is which, and why! r Yeast as a Food HEbreweries of Germany produee annually over 70,000 tons of yeast, which is for the most part wasted. For several months there have been going on systematic experiments under the direction of Prof. Delbriick. of the Berlin Institute for Fermentat'on Industries, for the purpose of finding some practical means for utilizing this product. Special attention has been directed to the prob'em of its possible availability as human food. There are a number of commercial preparations on the market which consist essentially of dried yeast; these combine the qualities necessary to adapt them to use as food, having an agreeab e taste and 'Odor and a chemical composition comparing favorably with other high-protein foods. When properly prepared, dry yeast keeps indefinitely without danger of deteri oni tion; and its high protein con tent would make it one of the cheapest foods. The slightly bitter taste eharacteristic of fresh yeast can be readily removed by treatment in the 'cold, before drying, with a solution of sodium carbonate. Messrs. Voetz and Baudrexel, of the Institute, havf determined its adaptability to the nutrition of man and other animals. The chemical composition of the dried yeast, ,as compared with average samples M beef, is given in the fol owing table: Dry Yeast. Beef. ,Vater ......................... 6.9% 72.5' Protein ........................ 53.4% 21.0'/ 0. Calories per lb. (approximate) . . 2,000 607 From the above it is seen that the protein value of the yeast is about two and a half times that of meat; and that the fuel value of the former is over three times that of meat. Experiments made in feeding dogs showed that 87.2 per cent of the nitrogen in the yeast is assimilated. 'Large quantities of this material , were used on the dogs without producing any symptoms Of inconvenience or disorder. Among the animals were some females suckling their young; these seemed to thrIve very well under the conditions of the experiment. A number of the emp'oyees 'Of the Institute replaced a portion of the meat in their diets with dry yeast powder using 2/3 ounce with each breakfast for sev-era· weeks. No unfavorable results were produced. 252 SCIENTIFIC AMERICAN September J G, 1 [ 11 How Electridty Is Aiding the Chemist (Cuntinued f1'Om puge 243.) methods for less than one dollar per pound. In 1889 Mr. C. M. Hall discovered and perfected his electrolytic method by means of which aluminium can now be sold at leEs than twenty·five cents per pound. The oxide of aluminium, a cheap raw material, though insoluble in most solvents and infusible at ordinary temperatures, dissolves in molten alkaiine fluorides like sugar dissolves in water. From this molten solution the metal is separated by the passage of an electric current, and appears at one electrode while the oxygen is set free at the other. The use-of alum:nium where lightness and strength are desired as in automobile and airship construction is well appreciated, and to it; cheap production much of the success in thesc indust, ies depends. Heat From Electricity.-Although heat derived from electricity is very many times more expensive than heat obtained by the burn'ng of ordinary fuels. there are two conditions which make electrically generated heat of great service to industrial chemistry. These are: 1. Heat generated within the zone of chemical reaction. 2. Heat generated at a temperature higher than that attainable by burning fuel. I.-In the great majority of chemical reactions, owing to the necess:ty of carrying away the waste gases produced by combustion, the heat thus generated must be conducteLl through a containing wall to the material undergoing chemical action. Not only is this in itself lIasteful of fuel, but frequently the high temperature llceessary on the outside of the container is so destrucIive of the containing vessel as to render the cost of cp"ration prohibitive. Since when an electric current passes through a conducter of high resistance great 1Ieat is generated in the conducter it is only necessary to place this conducter within the container in order tc, generate the heat at the point where it is needed. The walls of the container can thus be maintained at 3. much lower temperature than would otherwise be the case, which greatly prolongs their life. An example of the use of electric heat generated within the reacting vessel is in the manufacture of phosphorus. Although it was known for many yeats that a mixture of sand, coke and bone-ash when highly heated would produce phosphorus, the reacting mass so soon destroyed the containing vessel as to render tho process a failure.. By passing a current between carbon electrodes in a firebrick furnace, anLl feeding the mixture in such a way that the walls of the furnace· are constantly protected by some of the unacted upon charge, the process is made continuous and the cost of the material greatly reduced. All of the plusphorus of the great match companies is now made 1n this way. A nother example of the use of internal electric heatillg is in the manufacture of carbon-disulphide, a liquid lised in large quantities in protecting wheat and other Irain from the weevil. This chemical was formerly made by passing sulphur vapor over hot carbon in an i lOll retort. These retorts lasted so short a time, that the price of carbon-disulphide was never less than tventy-five cents per pound. By heating the earbon to incandescence by an electrie current the retort may be replaced by a firebrick furnace of large size and the material made so cheaply that it is now sold for less than four cents per pound. But by far the most important application of interIlal electric heating is in the manufacturing of steel. The older methods of making steel by the Bessemer and open hearth processes while capable of turning out an immense tonnage are both limited in the extent to which a steel free from dissolved gases, oxides and other undesirable constituents can be produced. The gases of combnstion are always present to contaminate the product. When made by the so-called crucible method, in which an amount not over 100 pounds is melted in a graphite crucible, a high grade product is obtained, but the cost is necessarily high. By the application of the electric furnace to steel making a gap which has long existed will be fill"d and a steel better than the open hearth but cheaper than crucible Courtesy Metaltw"(icaL allcL Chemical ElI(inenll(. Tapping a silicon furnace. !teel will be offered the consumer. There are a number of ty"pes of furnaces in operation in both America and Europe, some having a capacity of fifteen tons. Doubtless the' most important field for the electric furnace in the steel industry is as a finishing furnace for the Bessemer converter. This method is already, in use in the United States and is apparently giving very promising results, combining, as it does, the very cheap preliminary refining in the Bessemer process with the perfect finishing condition of the electric furnace. The great usefulness of the electric furnace in the preparation of a high grade steel at moderate cost is only beginning to be realized. 11.-The temperature attainable by the combustion of fuel is naturally limited to the dissociation temperature of the product of combustion; in other words, to the temperature where the carbon and hydrogen of the fuel will no longer combine with the oxygen of the air to generate more heat. This is approximately 2000 deg. C. In the electric furnace the heat generated by the passage of the electric current is limited only by the amount of electric energy available, and the volatilization point of the material forming the conductor. Carbon does not break up until a temperattu8 of about 3.700 deg. C. is reached, anL henee a temperature of this hitherto unthinkable intensity may be realized. With such an enormous temperature, or even much below this upper limit, many reactions are possible which do not take place at the maximum temperature attainable with fuel, and the working horizon of the chemist is thus greatly widened. Calc·tum Carbide. - The great chemist Wohler some fifty years ago made calcium carbide by uniting metallic calcium and carbon, and generated from it the won·· derfully brilliant illuminator, acetylene gas. But it was not until the advent of the electric furnace that calcium could be obtained direct from its ore, and lime and calcium carbide produced in large quantities. It is made very simply by heating to a very high temperature a mixture of lime and coke, or other form of carbon. The product is tapped in the molten condition from the furnace much as is the case with cast iron. The magic of the electric furnace has transformed the dull and slow burning coke into a compound which with water yields a gas brim full of energy and capable of giving a light of the greatest brilliancy. A new use is developing for calcium carbide in the fixation of atmospheric nitrogen. The plant world might paraphrase the lament of the shipwrecked mariner and say “Millions of tons of nitrogen and not one pound to use.” Although the air is 80 per cent nitrogen, it is not in a form available for plant growth. It has been found that when this nitrogen gas is passed over moderately heated calcium carbide, a union takes place, and a compound of calcium carbon and nitrogen called calcium cyanamide is formed. Under certain conditions this compound is a nitrogenous fertilizer and can be used instead of other forms of fixed nitrogen as a food for growing crops. A large plant for the manufacture of cyanamide has lately been finished at Niagara Falls, Canada. Carborundum.-A second carbide, but one entirely different in its properties is known as carborundum. This is made by uniting silicon and carbon at a high tLmperature, and forms an exceedingly hard mass which is used as an abrasive, much as emery is used. A mixture of sand (oxide of silicon) and coke is placed around a resistor of carbon and highly heated. After the furnace has cooled a mass of beautiful crystals, brilliant in color and exceedingly hard, is found concentric with the carbon. This mass is pulverized and worked up into abrasive objects of all kinds and is known and used the world over. Again the magic of this intense heat has produced from common sand and coke, a mass of brilliantly beautiful crystals; a splendid butterfly from the common grub. Graphite.-If in making carborundum the temperature is carried too high, instead of masses of the carbide of silicon there is found only the carbon constituent; but this is now in the form of graphite. This observation gave Mr. Acheson, the inventor of carborundum, a due which when followed out produced what is universally known as Acheson graphite. Before this discovery we were dependent upon the graphite scales obtained from Ceylon and Siberia, which had to be laboriously worked up into the finished article. Now the article, whether it be a crucible, electrode or what not, is formed of coke and pitch, and when baked is intensely heated in an electric furnace when it is converted into the purest graphite. This method of forming graphite electrodes has been an inestimable boon to the entire electro-chemical profession and has been an important fador in the progress of the art. SUcon.^-Instead of reducing the silicon from sand (oxide of silicon) and then combining it with carbon to form carborundum, it has been found possible to so conduct the operation that the metal silieon is formed in large quantities. A few years ago the element was a curiosity, now it is made and marketed by the ton. Space forbids extending the list of applications of electricity to chemical industry, but enough has been written to demonstrate the marvelous development which has taken place in the last fif'een or twenty years. What the future holds for the enterprising m-vestigator, no one can foretell