The sewing-machine man probably left a few months too soon; it is difficult to introduce anything new in a backward country, but perseverance is sure to bring its own reward.

Among enterprises which appear to me likely to succeed in Persia, I would suggest a combined agency for English cutlery, hardware, and fire-arms. All these articles of English manufacture are highly prized in Persia, but I know of no warehouse where such goods are kept in stock. A shop for carriage building, light iron work and repairs would, I think, find full and remunerative employment in Tehran. Spades, axes, files, and saws of good make and material are almost impossible to obtain; good English cloth and high-class fancy textiles are hardly to be found at all in the bazaars, and glass-ware, domestic and fancy, is almost entirely supplied from Bohemia by the Trebizond route. The

markets are well supplied with cotton goods, and the enterprise of an English firm has already developed an important business in the manufacture of carpets.

I think I have said enough to show that there is room for the merchant who proceeds with caution. I am also confident that many profitable industries might be started, though on a small scale at first; and I would instance, as possible openings, the collection and proper packing of dried fruits, the cleaning and pressing of cotton, the washing, sorting, and packing of wool, the revival of the silk industry and manufactures, and the erection of oil and flour mills.

In conclusion I will only repeat the old English proverb, "Strike while the iron is hot." I think the iron is now hot in Persia, and I hope to see my countrymen striking with precision, caution, and perseverance. -Nineteenth Century.

AMONG the traditions and legends which time has consecrated, and which have been woven into the texture of barbaric and civilized religions, the common essence of which is the exploration of everything, those on the origin of life and death have large place. The events that touched man closely in his personal surroundings were the subjects of his earliest guesses, and colored his interpretation of more remote phenomena.

But the explanations which satisfy an uncritical and pre-scientific age no longer pass unchallenged by an age which is content rather to confess ignorance than to accept theories which do not square with facts. And, so far as the origin of life is concerned, the veil remains unlifted. Schwann's discovery of the cell as the basis and theatre of vital function transferred the problem of life's beginning from the organism to the unit of which it is built up, and it seemed as if the secret lay within grasp. But, as Dr. Burdon Sanderson remarks in his Address to the Biological Section of the British Association at its recent meeting, that which has served to explain so much remains unexplained. "Our measurements are more exact, our

methods finer, but these very methods bring us to close quarters with phenomena which, although within reach of exact investigation, are, as regards their essence, involved in a mystery which is the more profound the more it is brought into contrast with the exact knowledge we possess of surrounding conditions."’

That knowledge is, however, not dumb respecting the origin of death. There are differences of opinion as to the causes whereby death has come into the world, but there is common agreement as to its universality. It is concerning this that we have erred. There are living things, as the sand by the seashore innumerable, which have escaped, and will continue to escape, the common lot, at least until a frozen or frizzled earth shall make all life upon it impossible. They are not indestructible, for obviously severe injury, enemies, subjection to intense heat, to poisons, and other agencies, may destroy them. Neither do they escape that molecular death which is a condition of life everywhere, in the destruction of old mankind and its replacement by new mankind. What is meant is, that since the beginning of their life on this planet that

life has known no death by senile decay or by definite arrest. Among them there is not, as there is among other organisms, procession after procession of mortal generations; so long as the conditions which are necessary for their life are fulfilled they continue to live, and they thus carry the power of an endless life in themselves. Unlike Tithonus, to whom the gods gave immortality, but withheld from him the blessing of eternal youth, they sigh not for "the lot of happier men that have the power to die," for, while all else waxes old, as doth a garment," they remain the same, fresh with the freshness of unfading juvenescer.ce. Well might they, had they but mouths, smile at the claims of long descent which we higher organisms, in our pride of birth, are ever vaunt ing; as it is, we come and go, shadows pursuing shadows, and these organless automata reck not, for before Homo pithecus they were. If not, like Wisdom herself, brought forth "before the mountains," many of these among our mightiest ranges are their juniors, uplifted from waters where they flourished æons ago. Untroubled by anxious search after an elixir vita, by haunting dread of death, or by melancholy born of dyspepsia, for them, not by them, has been solved the riddle of the painful earth; to them given the glory at which Virtue aims, of "6 going on" and "not to die." Only one drawback have they to their immortal life: they do not know that it is theirs; could they know it, that moment would it be taken from them.

But let us advance from the vague and general to the precise and special, and describe in detail what manner of things these are.

Everybody who is interested in his ancestry knows that living things are grouped under two main divisions-the one-celled and the many-celled. The one-celled among animals include the lowest and simplest forms, and the many-celled among animals include all organisms from sponges upward to human beings.

Now it is the one-celled which alone are immortal, and the evidence of this lies in their structure and process of multiplication. Both characteristics are well shown in the Amoeba, which may be taken as a type of all unicellular forms.

This organism is a minute, jellylike, irregularly-shaped particle of granular pro

toplasm, with faint approach toward unlikeness in parts in an external layer and in a nucleus toward the centre. It lives in water, and is constantly changing its shape, whence its name, moving about by pushing out blunt pseudopods or false feet. It takes in food and ejects undigested particles at any point of its body; in brief, every part does everything, performing all the functions of life as fully as the higher animals, the differences between them and it being in their highly specialized response to surroundings. For it also responds to these, the response taking the simple form of change of shape, in which lies the germ of the complex nervous systems of many-celled organisms. Sometimes, under certain conditions-as of drought, frost, and other adverse influences-it dries up, investing itself in a cyst or wall-a process known as encystment-during which it continues in a torpid state, resuming active life when favorable conditions recur. In brief, its state is one of sleep, the ape of death. It sets at defiance the rules of arithmetic in multiplying by division. When, by the assimilation of food, it has reached a certain size, it divides equally at the kernel, or nucleus. The protoplasm distributes itself around each nucleus as the two part company to grow and divide again in like manner, and so on ad infinitum, each half being a separate individual exactly like its fellow, and passing through the same stages of growth and fission. There is nothing novel in this description of the behavior of one-celled organisms, whether they be animals or plants; the novelty lies in the inference deduced therefrom, that death is not, as has hitherto been commonly assumed, an inevitable attribute of living matter, but that it has been acquired as an adaptation which first appeared when, in consequence of a certain complexity of structure, an unending life became disadvantageous to the species. This theory has been expounded and supported with skill and clearness by a distinguished biologist, Dr. Aug. Weismann, in some papers on the Duration of Life and on Life and Death, forming part of a remarkable volume, entitled Essays upon Heredity and Kindred Biological Problems, recently issued by the Clarendon Press. Dr. Weismann contends that the process of multiplication by fission does not involve the death of either part.

There is no cessation of vital functions; each part starts on an independent career, without break of continuity, and possessed of the same constitution. "There are,"

Dr. Weismann remarks, "no grounds for the assumption that the two halves of an amoeba are differently constituted internally, so that, after a time, one of them will die, while the other continues to live. Such an idea is disproved by a recently discovered fact. It has been noticed in one of the foraminifera, and in other low animals of the same group, that when division is almost complete, and the two halves are only connected by a short strand, the protoplasm of both parts begins to circulate, and for some time passes back ward and forward between the two halves. A complete mingling of the whole substance of the animal, and a resulting identity in the constitution of each half, is thus brought about before the final separation" (p. 26).

Neither can we say that the parent animal has died, unless it is also maintained that the man of to-day is no longer the same individual as the boy of twenty years ago. In the growth of man neither the structure nor the components of structure remain precisely the same; the material is constantly changing. But the individuality persists, and this holds equally good of the primordial amoeba, as of somewhat more highly organized one-celled animals, such as the infusoria, which possess a rudimentary mouth and short gullet, through which food and oxygen pass to the body cavity. If, then, the one-celled organisms are immortal, how came the many-celled, which have been developed from them, to lose this power of unending life? Obviously, through differences of structure; they kept not their first estate, must needs be other than they were. With the clustering of single cells together there necessarily resulted differences of position, some being outside and some inside; in other words, they were nearer to or farther from the influences of the surroundings or "environment."' Thereby arose differences of function. Their position determined the work which they had to do, which work, speaking broadly, is of two kinds; taking in and assimilating food, and reproduction. Hence it came to pass that the cells, after infinitely slow development of these functions-the function always determining the structure of the

but

organ which performs it fell into two groups-somatic or body-cells, and germcells. The body-cells, to which the work of nutrition fell, ultimately formed the larger group, and became, by slow degrees, more and more modified as their functions were subdivided. As these changes took place, the power of reproducing various parts of the organism was lost (although among certain lower animals this power is still retained in some degree), while the power of reproducing the whole individual became concentrated in the germ-cells alone.

These cell-unlikenesses were brought about by the action of natural selection, the agent which determines the fate and fortune of life-forms. From the dawn of life the structures best adapted to surrounding conditions have been victors; whatever features have proved useful have been seized upon by natural selection and secured dominance. The enormous mass of the lower forms have persisted to this day, because the balance established between them and their surroundings has remained unaltered. But wherever the balance between living things and their surroundings has been disturbed, new demands have been made upon them, to which they responded, or, failing that response, perished. Hence it is in the first complexity of structure, the first departure from simplicity, that the seeds of death

were sown.

For that death becomes a necessity. So far as its occurrence by natural causes is concerned, we know that as organisms get older (although this applies more to animals than to plants, in which the cells, as they becoine liquefied or converted into wood, are overlaid with new cells) their power of work and of renewal is lessened. The cells which form the vital fabric of tissues are worn by continual use; the waste exceeds the repair, and death ultimately ensues because a worn-out tissue cannot forever renew itself and because a capacity for increase by means of cell-division is not everlasting, but finite." Why there should be this limit to cell-division we cannot say, but it is clear that with the modifications of organs according to the work which they discharge there results a subtler structure which is less easy to repair and is shorter of duration. The onecelled organisms have found salvation in simplicity.

We are, therefore, driven to the conclusion that since there is, prima facie, no reason why growth should be limited, or why function should come to an end, death must have been brought about by natural selection, which determines survival or extinction from the standpoint of utility alone. There needs no showing that it is to the advantage of the species that individuals should die. Their immortality would be harmful all round; nay, impossible, unless vigor remain unimpaired, and the multiplication of offspring does not overtake the means of subsistence. "For it is evident," as Mr. Russel Wallace remarks in a note which he has contributed to Dr. Weismann's essay, "that when one or more individuals have provided a sufficient number of successors, they themselves, as consumers of nourishment in a constantly increasing degree, are an injury to those successors. Natural selection, therefore, weeds them out, and in many cases favors such races as die almost immediately after they have left successors, as e.g., among the male bees, the drone perishing while pairing, death being due to sudden nervous shock. In dealing with this question of the origin of death a distinction should be drawn between the body-cells and the germ-cells. While the functions and results of the cells which build up and nourish the body are limited to the life of the individual of which they are the sumtotal, no such limit can be imposed upon the germ-cells. Those which have fulfilled their function are endowed with actual immortality, because of the persistence of their influence through unnumbered generations. If in the natural death of the individual the germ-cells must also die, that natural death becomes a cause of accidental death to the germ-cells which are thereby prevented from exercising their functions of reproduction.

And, as the death of the individual becomes a necessity, being of advantage to the species, so is it with the duration of the individual life. Although there is some relation between size and longevity, the duration of the period of growth and length of life being, speaking generally, longest in the largest animals, there is no fixed relation between the two. The largest organisms live the longest, some trees reaching an age of six thousand years, and some animals, as whales, sev

eral centuries. And, after maturity is reached, larger animals require longer time than smaller animals to secure the preservation of the species. The explanation of this, as pointed out by both Leuckart and Herbert Spencer, is that "the absorbing surface of an animal only increases as the square of its length, while its size increases as the cube; and it therefore follows that the longer an animal becomes the greater will be the difficulty experienced in assimilating any nourishment over and above that which it requires for its own needs, and therefore the more slowly will it reproduce itself." We, however, find corresponding duration of life among animals of very different size. For example, the toad and the cat live as long as the horse, the crayfish as long as the pig, and the pike and carp as long as the elephant. In an interesting appendix, from which these and the following facts are quoted, Dr. Weismann cites the case of a sea-anemone which lived not less than sixty-six years. It was placed by Sir John Dalzell in a small glass jar in the Edinburgh Botanical Gardens in 1828, being then, as companions with other individuals reared from the egg period, fully seven years old. It died a natural death in August, 1887.

The rate at which an organism uses up its energy determines, in some degree, its length of life. But although inertness, as hibernating animals and pensioners show, promotes longevity, an active life is not necessarily a short one, unless, as folks say, the candle is burned at both ends. Where we find activity and brevity of life, this is due to the quicker attainment of the twofold purpose of life, the reaching maturity and the propagation of offspring. Birds are prominent examples of rapid energy-users, but knowledge of the ages which they reach in a wild state is very difficult to obtain and impossible to verify. A pair of eider ducks were observed to make their nest in the same place for twenty years, and it is believed that these birds sometimes reach the age of nearly one hundred years. A cuckoo, recognized by a peculiar note in its call, was heard in the same forest for thirty-two consecutive years. Humboldt tells of a parrot, concerning which the Indians said that they could not understand it because it spoke the language of an extinct tribe! Captive eagles and vultures have lived above a century, and Dr. Weismann refers

to the case of a falcon which reached the age of one hundred and sixty-two years. Among insects the range of life-duration differs widely, from the imago of certain may-flies, which lives only four or five hours, to the celebrated queen-ant which Sir John Lubbock kept alive for fifteen years, and which continued to lay fertile eggs, although there had been no male in the nest for fourteen years previously. But such longevity is confined to the females, which have to nourish their young until birth, a long life for the males being useless to the species.

This is the key to the whole question. Length of life is only ruled in minor degree by size and constitution, it is the needs of the species which determine it. In the larger number of life-forms the service which the parents render is at an end when offspring are produced in sufficient number to secure the species from extinction; then natural selection gets rid of them as cumberers of the ground. It is only where the duty of looking after the offspring falls to the parent that we find life prolonged beyond the reproductive period, as in the case of all mammals and birds.

Put into briefest form, the sum of what has been said is as follows :—

Death is not an essential attribute of living matter, because one-celled organisms never die a natural death.

Many-celled forms have a natural limit of life.

As many-celled forms are descended from one-celled forms this limit of life must have been acquired when the cells became modified into body-cells and germcells.

This modification was brought about by the action of natural selection, which has also determined the duration of the individual life.

That duration does not extend beyond the needs of the species.

The

Although death has entered into life, there has been no break in life-continuity since its appearance on the earth. highest life-form is derived from the lowest life-form through an unbroken chain. But we know life only as derived from life; we can assert nothing concerning its beginning; we know that it had a beginning, and that it will have an end.