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III. INFLOR ESCENCES and FLOWERS. IV. FRUITS and SEEDS V. SEEDLINGS. VI. GENERAL CHARACTERS.) ATHENEUM.-" A volume for which botanists and others owe their cordial acknowledgments to the Cambridge Professor, and which will mast them await with eagerness the publication of its companion on leaves and flowers." STUDIES from the ANTHROPOLOGICAL THE CAMBRIDGE PHYSICAL SERIES.-New Volume. London: C. J. CLAY & SONS, Cambridge University Press Warehouse, Ave Maria Lane. or the still living representatives of a disappearing species of plant or animal, is universally regarded as a Naturdenkmal; but in other cases, according to the country and locality, we find certain exceptions, for example, in north Germany the traces of glaciers on the rocks are among the greatest rarities, and must, therefore, be regarded as Naturdenkmäler. But on the coast of Scandinavia their occurrence in places is so READERS may naturally ask, "What is a Natur- frequent that there they are no longer Naturdenkmäler. and, since the word is a comparatively new one to the German vocabulary, necessitating its elucidation by the author even for German readers, it may not be out of place if we explain its meaning, as near as possible, in his own words. The usual meaning of "Denkmal" to the German mind suggests a monument or memorial to commemorate some famous personage or victory (for example, Goethe-Denkmal, Sieges-Denkmal). But in addition to this the title is often applied to outstanding works in science, literature, music, &c. Further, the remains of ancient buildings or works of art of whatever kind which have a historical, technical, or educative value, are spoken of as Bau- and Kunst-Denkmäler. Also the term is applied to prehistoric remains, such as lakedwellings, burying mounds, urns, tools and weapons of stone or metal; however, the author points out that all those Denkmäler are of artificial origin, that is, the result of man's work and ingenuity. The term Naturdenkmal has a wider application, and includes certain results of nature's handiwork, for example, the elaborately carved stone obelisk is a Denkmal of recent times, and the rough stone-block, erected by the hand of man to commemorate the dead, forms a prehistoric Denkmal; while the Glacial boulder, carried from afar in a former epoch and deposited on the plain by natural forces, forms a Denkmal of nature, or as the artificially built up cairn and rampart wall of a former age may form prehistoric Denkmäler, so the hill and mountain range, formed without man's intervention, are Denkmaler of nature. Also the whole natural landscape, with its various soil formations, with its water courses and lakes, with its special plant and animal communities, as well as single rare species and individuals of the original flora and fauna, represent "Naturdenkmäler." Although only virgin lands, together with their plants and animals undisturbed by man, should come within the strict sense of the term, still we must here and there allow a certain latitude in its application, because undisturbed localities are scarcely to be found in many of the modern cultured States. For example, any striking feature in the landscape, even if it is a deserted valley or village, must not be struck off the list. Also a natural forest growth which, by selfseeding, has followed the destruction of the original forest by man, must also be reckoned a Naturdenkmal. On the other hand, artificially planted trees, such as are found in many villages, avenues, and parks, no matter how interesting they may be, cannot be regarded in the strict sense of the term as Naturdenkmåler. In many cases the local conditions must be taken into account in reckoning any natural phenomenon as a Denkmal, for example, a part of the forest which has remained unexploited by man (virgin forest) In like manner the Cornel (Cornus Suecica) occurs in a few localities in north-west Germany, and in the east it is only found in one place, hence here it is a Naturdenkmal; but in north Russia, Finland, Sweden, &c., its occurrence is frequent over large areas, hence there it is no longer a Naturdenkmal. Similar examples may be given for many other plants and birds. From the foregoing it will be seen that a number of different factors determine whether a natural object can be reckoned a Naturdenkmal or not, and a decision can only be come to by taking the surrounding conditions in each case into account. The dangers which threaten those natural curiosities and rarities are many, and the author devotes almost one-half of the above memorial to an enumeration of many cases where, through ignorance, indifference, or natural causes, many unique Naturdenkmäler have been considerably damaged, if not entirely destroyed. As an example of the damage which may be done through ignorance or indifference, the author points out the way in which the most beautiful parts of the forests, within reachable distance from Berlin, are often rendered anything but attractive by the traces which trippers and picnic parties so commonly leave behind them. Frequently, also, the most beautiful spots are, disfigured by unsuitable and unattractive buildings, principally for the accommodation of visitors. The author also complains that many of the most picturesque hill-tops are disfigured by monuments and towers which are entirely out of harmony with their beautiful, natural surroundings. Then, again, the landscape is subjected to considerable disfiguration by the many devices employed by the advertising agent. Those in high authority are themselves not always free from blame. In one of the German Federated States it was at one time proposed that, in order to preserve the banks and channels of the water-courses, all trees and shrubs should be removed from the sides of brooks and streams. This movement was, however, happily frustrated, otherwise not only the æsthetic features of the landscape would have been entirely destroyed, but also many plant and animal communities would also have disappeared. The author then brings a long list of charges against tourists and visitors, showing how in many places characteristic plants of the coast and mountains have been almost entirely rooted out. The so-called sportsman, too, is responsible for the wanton destruction of many song-birds in certain parts of the Continent, especially Italy. The author further mentions the extremely regrettable manner in which the reindeer, now confined to Spitsbergen, Nova Zembla, Greenland, Siberia, &c., is systematically hunted and wantonly destroyed in the name of sport. Two cases are mentioned where well educated people in high posi tions organised expeditions to the native haunts of the reindeer, where in one or two days more than 100 head were killed, and the greater number of them allowed to lie and rot on the ground. The author further gives a long list of birds which are threatened with extinction unless something is done for their preservation. The dangers to which Naturdenkmäler are exposed through the drainage and reclamation of lands, utilisation of water-power, stone-quarries, exploitation of moors for peat, &c., also the dangers of scientific forestry, leading to the disappearance of all the virgin forest, the uprooting of certain plants for commercial purposes, trapping of birds for cages, and collecting by ornithologists, are too numerous to mention in detail. Around the ever-increasing centres of industry in Germany the pollution of air and water is becoming greater every day, with the result that plant and animal communities, as well as the whole natural landscape, are undergoing a rapid and radical change, which is necessarily accompanied by the disappearance of rare and valuable Naturdenkmäler. The proposals put forward by the author for their preservation occupy the larger part of the book. Generally speaking, they fall into three groups, viz. :—making a record of the various Naturdenkmäler for the different States throughout the Empire; providing for their protection in the various places; and making them generally known. In carrying out these proposals, it is necessary that the Government should take an active part by the passing of certain laws and allowing the active cooperation of different officials in the various departments. Also communities, societies, and private individuals are called upon to lend their aid. The various details in this proposed organisation for the protection of nature's monuments" seem quite reasonable and eminently practical, but with laudable modesty the author does not insist that they should be accepted in their entirety. He puts them forward more as a working basis, the details of which may be subject to alteration from time to time as experience and trial should suggest. He is, however, confident that the time will come when the " monuments" of nature will receive the same care and reverence as that which has for long been bestowed upon the monuments of early art and civilisation. 66 description of selected types of furnace arrangement, stokers, &c., illustrated by good diagrams, makes the whole a useful compilation. It cannot be claimed that any addition has been made to our general knowledge of the subject, for the importance of proper air supply, perfect mixing of the gases and air for combustion, the maintenance of a sufficiently high temperature for unchecked combustion, and other points have long been recognised in books dealing with boiler management. Smoke, in fact, is possibly not so much the result of ignorance as of conservatism and false economy. The book contains many statements in reference to water-tube boilers which few who have had practical knowledge of their working will altogether agree with. Thus "when moderately worked, some degree of safety, or at least a danger much less than attached to the discarded Howard boiler." Surely the rapid adoption of boilers of this type in the large electric lighting and power stations, engineering works, &c., is a sufficient answer to this. After a reference to the development and satisfactory working of water-tube boilers with anthracite coals in America, the authors refer to the same boilers being erected in this country to burn bituminous coal, and "being set exactly as in America, the results have been hopelesly bad, and the present smoke of London is due to this boiler more than anything else" (p. 19). It cannot be denied that the total sum paid in fines for permitting smoke from steam plant of this type has been fairly large, but does the total number of water-tube boilers in London, many of them giving grand results, bear any large proportion to boilers of the old pattern, in spite of the rapid adoption of the former in recent years? The statement we print in italics is far too sweeping and altogether unjustified. As the authors point out, in many cases boilers, presumably those in which the tubes are more nearly horizontal than vertical, were often set too near the fire, so that combustion was checked by the chilling action of the tubes; but this certainly does not apply to another type of water-tube boiler in use where the tubes are more nearly vertical than horizontal, for here ample combustion space is provided. Several excellent furnace arrangements are described and illustrated which provide for the maintenance of a high temperature until combustion is complete with these boilers, including the excellent one due to Mr. Miller. Engineers, however, do not seem very favourably disposed to much firebrick in the furnace, for it is not easy to ensure its standing the high temperature for any length of time, and water-tube boiler makers rather fight shy of such arrangements owing to the excessive heating of the lower tiers of tubes. Closely connected with this question is that of the chain grate. As mentioned by the authors, this practically fell into disuse until the advent of the watertube boiler resuscitated it, and yet we find the statement "it (the chain grate) must fail under the straight ascending flow of the usual setting of the water-tube boiler." Everything turns on the usual setting. There must be a number of unusual settings about, or it is not easy to understand why this grate has been so extensively adopted for these boilers. Certain it is |