disappearance of the forests has been gradual, from generation to generation, and no one generation has seen it all. Another reason is that a very large proportion of our population now resides in cities and takes little cognizance of the changes which have taken place outside of the city walls. If these forests had been destroyed by some great tornado or fire all at once, we should have been more generally impressed with the calamity of the loss. The loss, however, is none the less real because of our gradual awakening to it.

And as we wake up to this realization, we discover that with the disappearance of the forests there has been a concomitant loss in connection with our streams, for Nature is so intricately organized that she cannot suffer in one direction without being affected in her operations in another. In the removal of the forests, we have removed one of Nature's regulators of stream flow, with the result that the water courses have become spasmodic, and from streams of equable flow, have been converted into trickling rivulets or dry river beds in one season and destructive torrents in another. There are men living to-day who can recall the time when the creek, or river, which flowed through the old farm or the old town, supplied reliable power for the mill which now must be run by steam or not run at all.

There is also a strong belief that the removal of the forests has had a climatological effect, and that it has affected the rainfall; so that besides reducing our supply of wood for fuel and manufacturing purposes, and affecting the flow of our streams, it has affected our well-being in other physical ways.

These facts give vital importance to the conservation movement, which Mr. Roosevelt did so much to initiate and which Governor Dix and the Governors of the other States are so earnestly promoting to-day. Any agency which tends to help this movement along in a practical way, therefore, is a power for the public welfare, and such an agency is the arboretum.

What an Arboretum Is.

The word arboretum, meaning that part of a park or garden devoted to the growth and display of trees, is of English origin, appearing first, so far as we can learn, in a book upon arboretums

and fruit trees, published by J. C. Loudon in 1838. An arboretum is not a botanical garden, although the growing of plants may be associated with it. It is not a nursery for the raising of young stock for distribution, although some arboretums have a surplus of specimens which they are glad to distribute to other similar institutions for educational purposes. forestry, although it demonstrates the lie at the foundation of forestry. The modern school of forestry goes into the details of not only tree culture, but also of tree cutting and practical lumbering, which are not an essential function of an arboretum.

Neither is it a school of facts of tree growth which

An arboretum is a living collection of species and varieties of trees, arranged after some method, for the purpose of demonstrating their life and habits with a view to the availability of their kind for economic use or ornament under known conditions of growth. There are several methods of arrangement of arboretums. The trees or shrubs may be grouped according to their properties, or their uses, or some other principle, but usually after their natural likeness. The trees are intended to be specimens showing the conditions under which they thrive, and the collection is essentially an educational one. An arboretum may be constructed more or less with regard for the picturesque effect on the landscape, and some private arboretums are so planned, but as a general rule, the scientific value of an arboretum is largely proportional to the closeness with which it adheres to some systematic arrangement; and as a public arboretum is designed to facilitate the study and increase the practical knowledge of the public with respect to trees, its collections should be arranged for the special purpose of object teaching.

The function of an arboretum, therefore, is obvious. In one sense it is a living museum; in another sense it is a laboratory; but it is both of them on a large scale out of doors. In a museum the masterpieces of art are collected and studied and there art is encouraged. In the arboretum the largest of growing things are collected and studied and the planting of trees encouraged. In a laboratory, the growth and relations of microscopic organisms are studied, and the discovery or demonstration of a fact there is of benefit to the whole of mankind. In the arboretum are demon

strated the facts of larger growth, and those demonstrations, made within a comparatively small area, are of benefit to a great section of the country.

Other Arboretums.

Some rich men collect trees as they collect books or paintings for their own gratification, and there are several private arboretums in this country and Europe, but they are inaccessible to the general public, so that public arboretums are a modern public necessity.

One of the finest public arboretums in the world is that in the Royal Botanical Gardens at Kew, on the Thames River in the suburbs of London. The Botanical Gardens cover about 300 acres, of which the Arboretum covers 178 acres. As a public institution, the Kew Gardens are only about seventy years old. From about 1730 to 1840, they were occupied by Royalty. In the latter year, Queen Victoria relinquished them and they were placed under the control of the Commissioners of Her Majesty's Woods and Forests for the public good an instance of generosity of special interest in these latter days of women's interest in progressive movements. The Arboretum may be said to have been begun in 1762, when the Duke of Argyle's trees and shrubs were removed from Whitton Place to adorn what was then the Princess of Wales' Garden. During its early history, the Arboretum was enriched to an extraordinary degree by English voyagers like Captain James Cook, Sir Joseph Banks, and others, who brought home specimens from Australia, the Cape of Good Hope, Brazil and other widely separated corners of the earth. It is now perhaps the largest collection of hardy trees and shrubs known, comprising 4,500 species and varieties.

Ranking next to Kew, two of the more specialized public arboretums in Great Britain are the Royal Botanic Garden in Edinburgh and the Glasnevin Garden in Dublin. There is a respectable collection of trees in the Botanic Garden at Cambridge, and a small but select collection at Oxford. The latter, founded in 1632, is the oldest botanic garden in Great Britain.

The Jardin des Plantes at Paris, founded at the beginning of the seventeenth century, is a combined zoological and botanical garden, with an arboretum which has a well-known reputation, and there is a valuable private arboretum at Antibes in the French

department of Alpes Maritimes. Antwerp has a small but good arboretum, and at Amsterdam is another small but important one in which some valuable investigations are being made. There is also an important one at St. Petersburg. At Dahlen, near Berlin, the new Royal Botanical Garden has been laid out with a view to the establishment of a very large collection of trees and shrubs. Dresden has a good arboretum, and there is an extensive collection of trees and shrubs at Schonbrunn, near Vienna, but it is not what would be called an arboretum of the first class. One of the most interesting foreign arboretums is at Buitenzorg, the capital of a sub-residency in Java about thirty-five miles south of Batavia, where there is an extensive and famous botanic garden and arboretum around the splendid country palace of the GovernorGeneral. In many other Old World countries, not here mentioned, arboretums on larger or smaller scales attest their appreciation of the need and value of these institutions in civilized communities to stimulate and help the reproduction of the disappearing forests. In America, where the forests were naturally abundant and where their wholesale destruction has been recent compared with the destruction of the Old World forests, tree planting a century or a century and a half ago was simply the indulgence of the personal taste of the private gentleman. Washington had an arboretum on a small scale at Mount Vernon, where he displayed an adeptness at landscape architecture said to have been worthy of some of the finest estates in England. We also see glimpses of a similar tendency in some of the private estates in New York State, where men like Hamilton, and later Stephen Jumel, planted unusual trees upon their country places. The remnant of the imported cypresses upon the Jumel property in New York City, near the so-called Jumel Mansion (Washington's Headquarters) in One Hundred and Sixtieth street, and the avenues of old trees on various other old estates which might have been seen up to within a decade past, were evidences of the early tendency toward tree collection for pleasure. But it was not until the Arnold Arboretum was started at Cambridge, Mass., upon the foundation of the bequest of James Arnold, the friend of Emerson, that tree culture as a science may be said to have secured a foothold in America. There is a fine pinetum and shrub collection in the

public parks of Rochester; and a very promising arboretum in St. Louis, in connection with its park system. There is a fine arboretum in the Botanical Gardens at Ottawa, Canada, and there are smaller collections elsewhere, but there is no arboretum in the United States which fills the function which the Letchworth Park Arboretum is proposed to perform.

Letchworth Park Arboretum.

About a year before Dr. Letchworth died, he called to him a representative of the American Scenic and Historic Preservation Society, and laying before him a map of Letchworth Park, indicated certain improvements which he desired to be made eventually. These improvements included the forestation of certain areas. Then he took his consultant over the park and pointed out the tracts and requested that they be plotted on a map. Dr. Letchworth's views will be followed in the planting as closely as practicable, the species selected being varied according to the environment. As already intimated, Letchworth Park has an extraordinary variety of topography. This, in turn, creates such a variety of conditions that it is adapted not only to the growing of every kind of tree that can be grown in the State of New York, but also to the growing of varieties adapted to a wide range of country east of the Mississippi River. The Hon. George W. Clinton, an expert botanist and son of Governor De Witt Clinton, has stated that he found there a greater variety of flora than in any other equal area in the State. On February 4, 1907, soon after the announcement of the gift of Letchworth Park to the State, the New York Academy of Sciences, with a full realization of the educational possibilities thus presented, formally expressed its "sincere appreciation of this gift, which will give pleasure and be of important educational value for all time to the people of the State of New York and to visitors from other states and countries."

The principle upon which the Letchworth Park Arboretum is established is that it shall consist of a permanent collection of the various species of the world's timber trees likely to thrive. in this northern climate, planted scientifically, to test their value and illustrate the processes of development, so supplying not