WE generally think of the survival of the fittest as a principle which operates in time, bringing about those changes in biological species which are implied in the term evolution But the same natural selection which in time causes a closer adaptation of the organism to its environment is also potent in regulating the distribution of the several types and species in space. For, as climatic and other conditions vary according to the locality, the selective infuences at work at each point of our globe differ correspondingly from place to place, and the material selected, the surviving type, thus becomes a function of geographical position. The white man of the temperate zones is ill adapted for the torrid climate of central Africa, where nevertheless thrives, physically at least, the dusky native. The latter, again, when transplanted to our climate, proves less fitted for the battle of life than the white race, as is shown by his greater death rate and liability to certain diseases. But selection does not operate through death rates alone. Let us make a seeming digression, borrowing an example from physical chemistry. The chemist separates the more volatile constituents from a mixture by establishing local diferences in temperature in a suitably constructed system: the hot portion is called a retort, the cold a receiver. The mixture is heated in the retort, and presently the volatile vapors pass over into the receiver, where they condense to liquid. We need stretch the meaning of the term very little to say that the volatile liquid is not “adapted” to the conditions of high temperature which prevail in the retort, and is thus “weeded out” and converted into vapor. In the cooled receiver the conditions are diferent. Here the liquid is stable, and can subsist indefnitely. This is not unlike what happens in the living world, and with the human race. In the course of time the population of Europe has increased until, for very crowding, the struggle for existence has become much intensifed, however much it may have changed in character. The opening up of a new world across the seas has furnished a vent whereby some of the surplus has been able to escape to a less populous region. And just as in the still of the chemist, the substance which passes over into the receiver is not the same in composition as the material originally introduced into the retort, but contains a greater percentage of the more volatile constituents, so we may naturally look for a more or less marked diference between the overfow from the old world which has settled on this continent, and the residue in the home countries. We should, in fact, expect that the settlers, and presumably through hereditary infuence their descendants also, would represent the more “enterprising” element of the original population. And indeed, a strong spirit of enterprise is by common consent one of the most marked characteristics of the American nation. Somewhat less obvious, though none the less interesting, is a similar efect which has been observed in the old world. De Candolle in his “History of Science and Savants, illustrates by a number of very remarkable examples that the refugees, who, for holding fast to their personal convictions in the face of popular opinion, were expelled from their home countries during the troublous times of the sixteenth to the eighteenth century, have, together with their descendants, contributed over four times the normal share to the world's army of scientifc men, thus bringing a rich reward to the countries which ofered them shelter. The practically absolute sterility of Spain in the feld of science has been attributed to the infuence of the terrible Spanish Inquisition, which very effectually stifed all independent thought, and killed of every individual in whom the divine thirst for truth was clamoring to be satisfed. It must ever be a cause of universal regret that some members of that same organization which did so much to cultivate art and learning in the middle ages should, in mistaken zeal and with the crudity characteristic of their epoch, have dealt so little sympathy to some of those who helped to lay the foundations of modern science. Perhaps the most extreme case of the segregation of a special type of individuals by a process of “distillation” into a locality widely difering in character from the abode of the main body of the species, is presented to us when we look at a map of the polar regions, such as appears elsewhere in this issue. Here we may follow the tracks of intrepid wanderers, who braved the hardships and perils of that barren waste of ice and snow which guards the earths poles from the approach of inquisitive man. N one but the most venturesome and skilled explorers have found their way into this pale; here is selection indeed, and every man in this territory a hero. The Toll of Aviation: A Remedy THE passing the other day of the century mark in the number of lives lost in aviation calls to mind the pioneers whose lives were sacrifced needlessly in the development of this great science. The last of these to lose his life as a result of his personal experiments was “Prof. John J. Montgomery, of Santa Clara College, Cal., who was killed the 31st day of October, while trying out one of his gliders. It is a peculiar coincidence that Prof. Montgomery, who had built and operated successful gliders before the Wrights began their experiments, and who, by releasing a following surface monoplane glider from a balloon in 1905, had enabled Daniel Maloney, the aeronaut, to make the frst motorless fights of a quarter of an hours duration, should fall to his death only a few days after Or-ville Wright had achieved success along these lines and had risen from the ground and remained aloft 93; minutes without the use of any motive power save gravity and the wind. A parallel coincidence was seen in the death of Prof. Langley just after the Wrights achieved in December, 1903, what he had striven so hard and earnestly to accomplish. When we look back over the list of pioneers who have gone to their deaths as the result of their unconquerable desire to fy themselves, we deplore this unnecessary sacrifce and wonder how much more advanced we would be to-day if we still had Lilien-thal, Selfridge, and Nieuport. Perchance the great German would have found ere this a way to utilize the intangible ascending currents of air as Or-ville Wright has just utilized a 50-mile gale and thus have set us all soaring in bird-like fashion every man on his own home-made monoplane. Oh, that some means were found of communicating with the dead, that they might transmit to us the secrets and vast knowledge they have taken with them! How much faster the world would move forward in all the sciences and arts! But since such is not the case, it behooves those talented men who still remain not to jeopardize their lives by taking unnecessary risks. The accident that snatched away Lieut. Selfridge came within a hair's breadth of claiming Orville Wright also, while in his recent glider experiments he has had some rather close calls. The death of Prof. Montgomery so soon after, shows that danger lurks even in a motorless machine; while Glenn Curtiss should remember Manley's miraculous escape from drowning when the Langley aeroplane was launched from a house-boat, and should not personally take even seemingly slight risks with his hydro-aeroplane. The “Father of Aviation” in America the late much-loved and esteemed Octave Chanute, followed the proper course when he secured alert and active young men such as Avery and Herring to do the real experimenting. The same was true of Prof. I.angley, who was fortunate in securing the services of so eminent a young engineer as Charles M. Man-ley-a man capable oj constructing both motors and aeroplanes, and of fying them when built. H Edouard Nieuport had not dared to demon- strate personally for some ofcers his marvelous monoplane in a treacherous, gusty wind, he might again have produced a winner of the international speed race. The lamented Capt. Ferber is another pioneer who could not resist indulgence in the new, fascinating science. Had he studied it by proxy as did his fellow-countryman, Chanute, the aviation world would no doubt have had the beneft of his active brain for many years longer. The Food Value of Bread A LTHOUGH mankind has made use of bread in some form or other for several thousand years, there still remains much unknown about the food value and about the relation to digestion of this universal staf of life. An English study of the subject has just been completed, by a committee of the Local Government Board. This committee made use of much of the work done by experts of the U. S. Department of Agriculture. The old controversy between the advocates of roller-mill four and the defenders of stone-mill four need never again be revived, in view of the results obtained by a scientifc analysis of meals produced by the two processes. Not only do the roller-mill fours show a larger percentage of available nutrients, but the best grades of wheat-the so-called “hard wheats” -cannot be utilized at all in the old-fashioned stone mill; and the fours having the best “baking qualities” are produced by the roller mills. Roller-mill fours are also the whitest fours, which appeals to many on the esthetic side. Notwithstanding the enthusiasm of many apostles of whole-wheat bread, the fndings of the commission will rob them of some of their converts. It is found that the presence in food of bran-the outer coverings of the wheat grain-may be advantageous under special circumstances; but that in general it is an undesirable element in bread. Not onlv is the bran itself indigestible, but it interferes with the digestion of other nutrient factors in the food. For example, in one set of experiments it appeared that when milk was taken with whole-wheat bread three per cent less of the milk was digested than when it was taken alone, or with white bread. The most important point, however, is not the manner in which the four is manufactured, but the character of the wheat. That is, there is more difference between roller-mill, or stone-mill, fours from diferent kinds of wheat, than there is between the two diferent preparations from the same grain. It is at the same time in the direction of producing improved strains of wheat that the most progress has been made in recent years. Advocates of the virtues of bran in food often recommend the mixing of a small quantity of wholewheat four with the white four, in order to increase the percentage of mineral matter. The gain in salts to be obtained in this manner is, however, so slight, that a growing child would have to eat an excessive quantity of bread to derive any appreciable beneft from this method. With the mixed diet that is all but universal in civilized countries, we may well delend upon other parts of the ration to supply the additional mineral matter required by a growing child. Contrary to very common belief, this report declares that the diferent efects upon the teeth produced by diferent kinds of bread, are altogether negligible. The possibility for standardizing fom is considered to be very slight at the present time, especially on account of the (Eferent kjndr. uf wheat used in milling. Still, the diferences between the various kinds of wheat four on the market are not of serious importance. That whole-wheat fours may contain substances of value-quite apart from their infuence upon digestion-is believed by the committee to be a possibility worth considering; and they recommend scientifc investigation upon this point as well as upon several other problems that arose in the course of the inquiry. A New Use for Cactus A CONSULAR report from Montevideo suggests that the people of the southwestern United States, where cactus is abundant, and often a nuisance, might follow the example of the Uruguayans and utilize this plant in making whitewash. When traveling through the rural districts of Uruguay one's attention is attracted by the fne white color of the farm buildings, even during the wet season. The whitewash is made from the sliced leaves of the common cactus, macerated in water for 24 hours. To the creamy solution thus produced lime is added. When applied to any surface, a durable pearly white appearance is produced. Science Stamp-vending Machines in the German Postal Service.-Automatic machines for selling postage stamps are now extensively used in German post-of.ces, and have efected a considerable saving in the postal administration, although convenience to the public was the prime motive for their introduction. Nearly 50,000.000 stamps were supplied by the rachines during the past year, their value aggregating about $750,000. Surfacing Concrete Electric Light Poles With Mica.- Ground mica is now being used extensively for surfacing concrete in cement work. It has proved very efective for this purpose as it gives an artistic fnish to the work, and adds life and sparkle to the surface, taking away that fat, dead appearance that is common to concrete. About fve pounds of mica is sufcient to cover 100 square feet. The electric light columns in Lincoln Park, Chicago, were treated in this way. Crushed red granite was used with the mica, so that the fnished surface has the appearance of polished granite. The granite and mica surfacing material was applied to the inner surface of the square iron trough in which that part of the columns that was to extend above ground was cast. When the trough was flled, the top or lid was screwed down, crowding the concrete into all the lines and corners of the mold. After the cement had set perfectly, part of the mold was removed to permit the post to cure more rapidly. The post was not removed from the mold until it had set for 24 hours at least. After it was perfectly dry the surface was scrubbed with muriatic acid, to remove the cement on the outer face of the granite and mica and leave a clean surface closely resembling that of granite. An Imperial Chinese Printery.-A few months ago the Chinese government began to erect a modern printery that will require a total expense of $2,000,000. Construction of the building and installation of the printing-plant have been intrusted to American architects. The present monetary system of China is so complicated that it is really a very emphatic hindrance to the development of trade and industry. In accordance with this system every individual province emits its own currency, and the standard of value is diferent in every province. For a long time, .con!?6-. quently, a persistent efort has been made to devise and introduce a uniform standard of value for the whole empire, and the construction of the printery in Pekin begins the transformation of the collective monetary system of China. Two years ago the government sent Dr. Chen to Europe and America to study the machinery, and its installation, of the most efcient printeries in these countries, and in accordance with his report the governmental printery of the United States in Washington was selected as a model. It is hoped that the Imperial Chinese Printery may be fnished within two years so that it can begin work when Parliament opens in 1913. Besides other experts two American engravers have been employed already to supervise the installation of the plant and to instruct the Chinese in thl art Qf Ingraving. Engineering Our Excellent Lighthouse Service.-It is a curious anomaly that the United States, which possesses the smallest foreign-going merchant marine in the world, should possess the most perfectly-equipped and elaborate lighthouse service to be found on the coast line of any nation. During the past half century this service has cost $150,000,000, and its maintenance calls for the appropriation of about $7,000,000 annually. Panama Exposition Memorial Tower. -A concrete steel tower, which will be the loftiest structure, with the exception of the Eifel Tower, in existence, is to be erected at San Francisco in connection with the Panama·Pacific International Exposition, whkh will be held in that city in 1915. From the foor to the top of the fgure of Vidory, surmounting the shaft, the height will be 850 feet. It is to cohsist of a square shaft upon a base 232 feet square and 120 feet high. The shaft will measure 85 feet on each face. The estimated cost of the structure is $1,500,000. Daily Earnings of a Locomotive. -A writer in the Railway ana Engineering Review recently gave the interesting results of a computation of the average daily earning capacity of the American locomotive. The estimate took account of time spent in the repair shop, increased cost of repairs and renewals, and the cost of fuel, water and the engine crew. The average earnings per locomotive per day in the East are $124.84, and on the western roads, $130.84. The highest earnings in the West are those of the Santa Fe locomotives, which work out at $149.53 per day. The highest earnings in the East are on the Central Railroad of New Jersey, where the average is $147.06 per day. Steam Turbine Improvements.-The superiority of the reciprocating engine over the steam turbine, when a ship is steaming at low speed, is destined to disappear. At high speed the turbine possesses every advantage; but at low speed it is extravagant in its use of steam. Of the several systems of reduction gear by which the widely diferent economical speds of propeller and turbine are sought to be harmonized, the electric drive seems to present the most promise. A better method would b the proper combination of reciprocating engInes for low speed and turbines for high speed. The navy has under consideration a system of this kind which we hope shortly to present for the consideration of our readers. Our New Three-gun-turret Battleships •.-Plans and specifcations are now being prepared in the Navy Department for the two super-dreadnought battleships authorized at the last session of Congress. These ships, which will be named the “Oklahoma” and “Nevada,” will contain many novel features, the most important of which will be the introduction of the three-gun turret, of which there will be two, containing six 14·inch guns. The other four 14-inch guns will be carried in two-gun turrets. The armor plan has been worked out with great care; and we understand that these ships will be protected by a thickness of face-hardened armor which has never been attempted in any battleship in our own or foreign navies. Aeronautics Results of the Tests for Military Aeroplanes in France. -The preliniinary tests of the 29 machines entered in the competition for military aeroplanes in France have resuIted in the elimination of 5 of the 8 monoplaes and 14 of the 19 biplanes. Neither of the two triplanes-the Astra and the Paulhan-was selected. The machines which were scheduled to participate in the fnal 185-mile speed race on November 4th were the Morane, Nieuport, and Deperdussin monoplanes, and the Breguet, Savary, H. Farman, and M. Farman biplanes. We expect to publish a complete account of these tests in our next issue. Te Trans-continental Flight Nearly Completed.- On November 1st Aviator Calbraith P. Rodgers covered 177 miles between Wilcox and Maricopa, ArIz., and got within 400 miles of the coast. At Tucson, the half-way point, he met Robert G. Fowler, who arrived there October 30th on his fight from the Pacifc to the Atlantic, and who was delayed with Emgine trouble and an accident upon restarting. The two dauntless Wright pilots shook hands, congratulated each other, and hoped for better luck. Rodgers found a number of broken rollers on the propeller chains of his biplane, and was delayed at the start in replacing them. Then he had to breast a 30·mile head wind and to climb considerably to get through the 4,351-foot Dragoon Pass. He fought a head wind throughout the entire day, his time en route being 1% a;d just over 2 hours, respectively. November 2nd he few 35 miles to Phrnix in 35 minutes, and 105 miles to Stovall in 118 minutes, aided by a strong wind. He beat his special train by over two hours. Recent Aeroplane Fatalities.-The last month has witnessed the passing of the hundred mark in aeroplane fatalities. October 12th aviator Level fell to his death in a Savary biplane which he was piloting in the French army tests. His spine was broken and he died soon after. Two other French aviators. Horta and Germain-also fell the day previous. One was killed and the other fatally injured. The hundredth victim of aviation was Hans Schmidt, who fell at Berne, Switzerland, on October 14th, and was incinerated as a result of the ignition of his fuel. On the 21st ult. an aviator named Tacks fell and was killed near Hamburg. The loss which was most keenly felt in America, however, was occasioned by the death of Eugene Ely, the Curtiss aviator, at Macon, Ga., on October 18th. Ely was making one of those daring dips for which Hamilon became famous, when he miscalculated and struck the ground with terrifc force. He was thrown out and his neck was broken. Ely was using a machine without any front control, while he had been used to a biplane with a front horizontal rudder. The slower response of the former type to a movement of the elevator was doubtless responsible for Ely's death, although the immediate cause waS the performing of foolhardy tricks. On October 27th Jean Desparmet fell 600 feet in a 100·horse-power Bleriot military monoplane at Rheims, while on the 31st Prof. John J. Montgomery was kiIled in California.