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dale. I have carefully measured the proboscis of a specimen of Macrosila cluentius from South America, in the collection of the British Museum, and find it to be nine inches and a quarter long! One from tropical Africa (Macrosila morganii) is seven inches and a half. A species having a proboscis two or three inches longer could reach the nectar in the largest flowers of Angræcum sesquipedale, whose nectaries vary in length from ten to fourteen inches. That such a moth exists in Madagascar may be safely predicted; and naturalists who visit that island should search for it with as much confidence as Astronomers searched for the planet Neptune,—and I venture to predict they will be equally successful!

Now, instead of this beautiful self-acting adjustment, the opposing theory is, that the Creator of the Universe, by a direct act of his Will, so disposed the natural forces influencing the growth of this one species of plant as to cause its nectary to increase to this enormous length; and at the same time, by an equally special act, determined the flow of nourishment in the organization of the moth, so as to cause its proboscis to increase in exactly the same proportion, having previously so constructed the Angræcum that it could only be maintained in existence by the agency of this moth.

But what proof is given or suggested that this was the mode by which the adjustment took place? None whatever, except a feel

ing that there is an adjustment of a delicate kind, and an inability to see how known causes could have

produced such an adjustment.

I believe I have

shown, however, that such an adjustment is not only possible but inevitable, unless at some point or other we deny the action of those simple laws which we have already admitted to be but the expressions of existing facts.

Adaptation brought about by General Laws.

It is difficult to find anything like parallel cases in inorganic nature, but that of a river may perhaps illustrate the subject in some degree. Let us suppose a person totally ignorant of Modern Geology to study carefully a great River System. He finds in its lower part, a deep broad channel filled to the brim, flowing slowly through a flat country and carrying out to the sea a quantity of fine sediment. Higher up it branches into a number of smaller channels, flowing alternately through flat valleys and between high banks; sometimes he finds a deep rocky bed with perpendicular walls, carrying the water through a chain of hills; where the stream is narrow he finds it deep, where wide shallow. Further up still, he comes to a mountainous region, with hundreds of streams and rivulets, each with its tributary rills and gullies, collecting the water from every square mile of surface, and every channel adapted to the water that it has to carry. He finds that the bed of every branch, and stream, and rivulet, has a steeper and steeper slope as it approaches its sources, and is thus enabled to carry off the water from heavy rains, and to bear away

the stones and pebbles and gravel, that would otherwise block up its course. In every part of this system he would see exact adaptation of means to an end. He would say, that this system of channels must have been designed, it answers its purpose so effectually. Nothing but a mind could have so exactly adapted the slopes of the channels, their capacity, and frequency, to the nature of the soil and the quantity of the rainfall. Again, he would see special adaptation to the wants of man, in broad quiet navigable rivers flowing through fertile plains that support a large population, while the rocky streams and mountain torrents, were confined to those sterile regions suitable only for a small population of shepherds and herdsmen. He would listen with incredulity to the Geologist, who assured him, that the adaptation and adjustment he so admired was an inevitable result of the action of general laws. That the rains and rivers, aided by subterranean forces, had modelled the country, had formed the hills and valleys, had scooped out the river beds, and levelled the plains;—and it would only be after much patient observation and study, after having watched the minute changes produced year by year, and multiplying them by thousands and ten thousands, after visiting the various regions of the earth and seeing the changes everywhere going on, and the unmistakable signs of greater changes in past times, that he could be made to understand that the surface of the earth, however beautiful and harmonious it may appear, is strictly due in every detail

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to the action of forces which are demonstrably selfadjusting.

Moreover, when he had sufficiently extended his inquiries, he would find, that every evil effect which he would imagine must be the result of non-adjustment does somewhere or other occur, only it is not always evil. Looking on a fertile valley, he would perhaps say " If the channel of this river were not well adjusted, if for a few miles it sloped the wrong way, the water could not escape, and all this luxuriant valley, full of human beings, would become a waste of waters." Well, there are hundreds of such

cases.

Every lake is a valley "wasted by water," and in some cases (as the Dead Sea) it is a positive evil, a blot upon the harmony and adaptation of the surface of the earth. Again, he might say—“ If rain did not fall here, but the clouds passed over us to some other regions, this verdant and highly cultivated plain would become a desert." And there are such deserts over a large part of the earth, which abundant rains would convert into pleasant dwelling-places for man. Or he might observe some great navigable river, and reflect how easily rocks, or a steeper channel in places, might render it useless to man;-and a little inquiry would show him hundreds of rivers in every part of the world, which are thus rendered useless for navigation.

Exactly the same thing occurs in organic nature. We see some one wonderful case of adjustment, some unusual development of an organ, but we pass over the

hundreds of cases in which that adjustment and development do not occur. No doubt when one adjustment is absent another takes its place, because no organism can continue to exist that is not adjusted to its environment; and unceasing variation with unlimited powers of multiplication, in most cases, furnish the means of self-adjustment. The world is so constituted, that by the action of general laws there is produced the greatest possible variety of surface and of climate ; and by the action of laws equally general, the greatest possible variety of organisms have been produced, adapted to the varied conditions of every part of the earth. The objector would probably himself admit, that the varied surface of the earth-the plains and valleys, the hills and mountains, the deserts and volcanoes, the winds and currents, the seas and lakes and rivers, and the various climates of the earth-are all the results of general laws acting and re-acting during countless ages; and that the Creator does not appear to guide and control the action of these laws -here determining the height of a mountain, there altering the channel of a river-here making the rains more abundant, there changing the direction of a current. He would probably admit that the forces of inorganic nature are self-adjusting, and that the result necessarily fluctuates about a given mean condition (which is itself slowly changing), while within certain limits the greatest possible amount of variety is produced. If then a 66 contriving mind" is not necessary at every step of the process of change eternally

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