Popular Science Monthly/Volume 32/March 1888/Our Ice-Supply and its Dangers
|←The Antechamber of Consciousness||Popular Science Monthly Volume 32 March 1888 (1888)
Our Ice-Supply and its Dangers
By T. Mitchell Prudden
|Flamingoes at Home→|
By T. MITCHELL PRUDDEN, M.D.
IT is not easy to realize that the region which we now call New York was once a mass of bare, tangled rock, bound fast beneath vast glacial ice-fields, which, stretching away to the north and west, held all northern North America in the bonds of a dreary desolation.
The gigantic fissure through which welled up from the earth's center that vast mass of molten rock which we call the Palisades, had closed fast upon its sides long before the last reign of ice began; and when at length the cold era was established, and the great glaciers, with their slow, resistless flow, came sweeping down, year after year, over the top of the Palisades, across the rocks on which New York stands, and at last broke off and melted in the sea, the ice-mass, and the fragments of stone which it had torn loose in its progress and held fast along its sides and bottom, planed down the rocks over which it passed, and left upon their exposed surfaces broad grooves, shallow channels, and innumerable scratches, which to-day tell silently the story of that ancient reign of ice. The house-building furor is fast removing these ancient records, but in the upper parts of the island and on the top of the Palisades one still may see large numbers of glacier grooves and scratches.
How long this ancient Ice age lasted it would be useless to conjecture now; but at length the climate changed, and by little and little the ice relaxed its grasp. The stones and bowlders, with which it was so relentlessly grinding off the surface of the earth's crust here-about, dropped from its fingers and lay much as we may see them OUR ICE-SUPPLY AND ITS DANGERS. 669
now in some parts of the track of the North American ice-belt, scat- tered or piled in masses where the ancient moraines were gathered, miles from their kindred rock. And now over the surface of the bare, forbidding region, slowly as the ages passed, crept the verdure which, out of rock and air, was to recreate the world. Probably long before man made his appearance, on this part of the continent at least, the ice had all melted and gone to waste. He came, however, at last, the savage, the Dutchman, and — most perfect bloom — the New-Yorker.
In the early days of New York village life the stolid citizen was far too busy to spend much thought on luxuries, in adapting himself to the untried conditions of the New World and maintaining his foot- hold against the wiles of his savage neighbors. His gustatory sense had, with characteristic directness, been contented for the most part with plain unadorned rum when it felt the need of extraneous stimu- lation, and this and other simple drinks were either taken au naturel or re-enforced by the addition of spices under the kindly offices of fire. Water, which the early citizen may, in moments of relaxation of the mental fiber, have playfully regarded as a beverage, was largely de- rived from wells, and thus might be had of sufficient coolness to be palatable under natural conditions.
Half a century ago twoscore wagons sufficed to distribute all the ice which was used in New York ; but the demand steadily increased, until now nearly three and a half million tons are harvested annually, in favorable seasons, in the vicinity of New York. Few realize how much the comfort and welfare of all classes, especially in the summer months, have come to depend upon that free use of ice which its abun- dance and cheapness make possible. Untold dangers from the con- sumption of spoiled meat and other fresh foods are warded off through its preservative action, and their market value largely reduced. And who can adequately realize the comfort and even life-saving agency of ice among the sick and injured ? When the charities of New York are summed up, the free distribution of ice-water in some districts of our city should not be reckoned as among the least important.
Perhaps of any single class of consumers of ice the brewers use the largest quantities, to control the high temperature which accompanies the fermentation of the wort ; but for this purpose processes of artifi- cial cooling have, to a considerable extent, replaced the natural ice. Ice-cream makers and market-men are also among the most important consumers. The experiences of the writer would hardly justify him in enlarging upon the multifarious concoctions into which ice enters be- fore they are handed by the white-aproned autocrats over the more or less attractive bars of our no longer temperate town to gilded and brazen youth and statesmen, or to their humbler confreres and con- stituents more commonly only dirt-adorned. On the whole, in spite of its not infrequent abuse when used for drinking purposes in large quantities and at unsuitable times, ice is one of the most indispensable
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of the accessories to modern life, especially in large towns ; and it is wholly to our credit that its free use has become a really noteworthy national trait.
New York has its ice-speculators and its Ice Exchange, and the Ice Exchange has its bulls and bears, who watch the thermometer and the weather as intently as their confreres in another market watch railroad-construction and the ticker. An ice-trade journal, published in Philadelphia, does valiant duty in endeavoring to establish the po- sition of the ice-trade among the great industries of the world.
From twenty to twenty-five million tons of ice are annually har- vested in the United States, and not far from fifty million dollars are invested in the business. It is probable that we use more ice annually in the city of New York alone than is consumed on the whole Conti- nent of Europe. It is said that, if all the ice-houses on the Hudson River below Albany were placed side by side, the line would be not far from seven miles long ! If we estimate the bulk of the entire amount of ice annually harvested in the vicinity of New York each year, wc find that, if piled in a solid mass one hundred feet square, it would make a column soaring nearly three miles into the air. We have thus a veritable return of the Ice age — on quite a small scale, it is true, in comparison with that which Nature brought about by tilting up the strata and lowering the temperature of North America a few degrees ; but then man always cuts a rather sorry figure when his " tinkerings " with the elements are brought into contrast with the re- sults of Nature's wholesale and forceful work. A certain amount of ice is brought to New York from Maine each year, but the quantity is not large except after open winters, when the crop hereabout has been a poor one. Norwegian ice, with which England is largely supplied, has been at times brought here in small quantities, but under ordi- nary conditions it can not compete in the market with the domestic product.
Rockland, Highland, and Greenwood Lakes ; Swartout Pond, near Rockland Lake ; an artificial pond called Lake Meheagh, on Yerplank's Point ; Tuckahoe Pond, on the Bronx River ; Yan Cortland Pond, in the new Yan Cortland Park ; Ice or Hinkley's Pond, on one of the small tributaries of the Croton River ; and Lake Mahopac — all furnish varying amounts of ice for our market. But the Hudson River be- tween Poughkeepsie and Albany forms the principal source of our supply. In the earlier days of ice-harvesting on a large scale upon the Hudson there was a good deal of quarreling among the representatives of the various companies as to their rights to particularly favorable ice- fields, and lively skirmishes over evanescent and uncertain boundary- lines took place between the employes of rival companies, with the natural sequelte of broken heads and noses. But with legally ac- quired rights to the water-front on or near which the storage-houses are built, and the occupation year after year of particular tracts upon
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the ice, these picturesque struggles, which recalled in little the fre- quent encounters between the retainers of rival houses in feudal times, have passed away, and the scene of personal encounters is mostly transferred to bai'-rooms. But the modern representative (God save the mark !) of feudal times now and again stirs up discord in the form of strikes and their retroactive accompaniments among the ice- harvesters.
The days when the most approved manner of storing ice was to dig a hole in the ground, fill it with ice, pack straw around it, and cover it tightly, leaving some primitive mode of access, have long since passed, and some of the larger storage-houses are not only moderately taste- ful in their construction and ornamentation, but are fairly imposing in size. The better houses, mostly of wood, have efficient drainage at the bottom. The walls are hollow, containing an air-chamber, and within this a chamber filled with some non-conducting material, such as sawdust or hay, while above is a loft with abundant ventilation. The larger houses are divided into a number of rooms, so that when they are opened for the removal of the ice the whole mass need not be exposed to the warm air which enters.
The cakes of ice, which in this region are cut of a uniform size of about twenty-two by thirty-two inches, are usually laid flat, a solid stratum at the bottom. Above this they are placed on top of one an- other with two or three inches of space between their edges, the joints being broken every few tiers, as in masonry, by allowing the cakes to lap over the joints below. The object of the space between the edges of the cakes is to prevent their freezing together, for if this occurred their removal would entail a good deal of additional labor in breaking them apart, and a large loss of ice which would be chipped off in the operation. When the houses are about full, a solid layer of cakes is laid on top, so that the air may not circulate between them, and the whole is covered by hay. A varying number of smaller buildings are usually clustered about the storage-houses, such as engine-house, tool- house, shop, barn, and often the boarding-house for the men.
But let us leave these dry details and get out of doors, lest Winter should steal a march on us, and we should lose those first delicate crys- tal spiculse shooting out from shore and rock with which he commonly begins his work alike on lake and stream and pool. Who does not know those fragile ice-fringes, losing themselves in the open water, which the first frosty nights in autumn leave behind often only to fade away in the next day's sun ? But when at length, after these early, playful exhibitions of his gathering power. Winter really bends him- self to his work, the crystals grow longer and thicker, their sides join, and finally the completed film formed along the surface shuts in the water, and his dominion is complete. Now his tactics change. The capriees which he has displayed as the long crystals stole out in ever- varying directions from the shore are subdued, and the stern Avork of
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strengthening his fetters fairly begins. After the first film of ice is formed, the freezing goes on directly downward as the heat from the water radiates off into the colder air above. The direction of crys- tallization has changed, and is now at right angles to that in which it began. Unhindered radiation of heat from the water out into the air is the secret of the continued formation of ice. If anything occurs to prevent this, the ice stops forming beneath. A fall of snow upon the already-made ice greatly retards its continued formation.
Some of the elder ice-harvesters still foster a feeble flame upon the broken altars of the old star-worshipers in their belief that the cold rays from the winter moon and stars favor in some mysterious way the growth of their ice, since this forms best on the clearest nights. Who would dispel this chaste illusion by suggesting that the clouds which draw themselves at times over the faces of their gentle deities delay the fruition of their hopes simply by pi-eventing the escape of the earth's heat off into space ? In the vicinity of Kew York, where open winters are so common and changes of temperature are so great and frequent, the formation of the ice is a matter of the greatest solici- tude to the ice-farmer, upon whose vigilance and judgment may large- ly depend both the value and abundance of his winter's crop.
Let us suppose that Winter is fairly in possession along the river. The storage-houses, machinery, and tools for harvesting the ice are in order. Many of the horses which have dragged the last year's crop in its daily distribution about the town have been brought up on the retm*ning empty barges to recruit a little before their winter's work begins. The men who are to engage in the harvesting are beginning to straggle in to make their arrangements. A certain number of these are regular employes of the companies who work in town during the summer. Then along the Hudson many of the workers are farmers from the adjacent country, who, not over-busy in the winter, come down singly or in squads, looking upon their term of service to the ice companies as a sort of lark with a pecuniary bias. Then there is a large number of rovers, living, Heaven only knows how, through the rest of the year, who straggle along the river, work long enough to keep themselves drunk for a day or a week, and then brace up for an- other turn on the same or on a different field.
While all these forces are gathering toward the ice-harvesting centers, the superintendent is keeping a sharp lookout on the forma- tion of the ice. The field has to be staked out as early as possible in order to secure it against invasion by competitors. It used to be necessary to make a fence four feet high around a pre-empted ice-field in order to legally secure it, but stakes or twigs stuck in the ice four feet apart are deemed sufficient now.
While the weather is clear and cold, and the colder and clearer the better, all goes well with the growing crop as slowly the water yields itself into its crystal bonds, and the domain of the clear, solid ice creeps
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downward inch by inch. But this condition of affairs, quite ideal from the standpoint of the ice-farmer, is apt in this region to be eva- nescent. If the grip of the cold relaxes by day, the formation of ice may stop, and even a film of that already made may melt away in the water beneath ; but at night again another layer may be added, and so, with many halts, retreats, and slow advances, little by little the ice- mass thickens. But who would imagine that, written in the ice, as plain- ly as the sequence of geologic ages is written in the rocks, is the record of these alternate victories of heat and cold as they contended for the mastery of the water during the winter days and nights ? Strange as it may seem, the record is there, however, and, stranger yet, is written in air. Look at the edge of a cake of ice which has formed in com- paratively still water during such alternations of temperature as are common in our winters, and you will be very apt to see a series of bands of transparent ice, between which lie layers of tiny air-bubbles. In still water, when the ice for any reason stops forming for a time, bubbles of air from the water or from the bottom are apt to rise and collect beneath the ice, and when the freezing again begins they are entangled and held fast between the old and the new ice-layers, a per- manent record of the relaxation of the thrall of the cold long enough for their collection. In running water such bubbles are apt to be swept away, and the ice remains transparent.
While the ice is thus forming the ice-farmer looks on, his spirits rising in inverse ratio to the height of the thermometer. To the vagaries of the temperature he must reconcile himself as best he may. But let his btte noire, the snow — if so violent an antithesis be permis- sible — appear, and he will be on the alert at once. The snow-flakes, delicately adjusting themselves to one another as they settle down upon the ice, build up among their crystals myriads of tiny air-cavities, and the whole forms a veritable blanket which hinders radiation. It is warm for the same reason that a down comfortable is — it prevents the escape of heat. Now, what shall our ice-farmer do ? It does little good to swear at the snow, although he usually has recotlrse to this procedure first. If the already formed ice is thick enough to bear the teams, he may scrape the snow off, and then the freezing can go on. But if not, he sends his men over the field to cut small holes here and there through it ; the water wells up, flows over the top, forming a layer of slush, a good deal of the air is expelled, and the whole freezes, forming a whitish layer which is called snow-ice. This layer is whitish because of the air-bubbles which it still retains, but it conducts off the heat fairly well, and his crop goes on forming. This operation is called "tapping" or "bleeding" the ice. Ice which has a very thick snow layer is called "fat ice." This snow-ice is not as valuable as clear ice, for householders object to it because they fancy that it is not so pure, and the assurances of the dealers that the impurity is only air appear to have little weight. So the more responsible dealers usually find it vol,. XXXII. — 4r3
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for their interest to remove most of the snow layer. A little snow-ice ou the cakes, however, raakes them keep better. We shall see by and by that there are really very good reasons why the snow-ice from certain sources should not be used for drinking purposes.
At last the vicissitudes and anxieties of the growth of the ice-crop are over, and the " boss " decides that the cutting shall begin, A good deal of responsibility attaches to this decision, and many factors must be considered. If a good thick mass has formed, say from ten to fourteen inches, the sooner it is under cover the better. But if the weather has been tickle and warm, and the layer is only from four to six inches thick, it is a more difficult matter to decide. It is better to have six-inch ice in the houses than none at all; but if by a little delay two or three more inches could be secured, it would be an immense gain. But, on the other hand, while waiting for the added increment, warm weather or a freshet may suddenly come on, and the whole crop be lost. Repeated snows upon the ice are bad ; an untimely breaking up of the ice by a freshet is worse. But if, during the freshet, the whole field is swept away, there is often still a chance for a new crop to form. About the worst combination of misfortunes — and it is not so very infrequent — is for the ice to soften, to be all jumbled up and mixed with dirt and debris of various kinds from above by a freshet, and then, before this mongrel and well-nigh useless mass can be swept down stream and away, to have the whole thing freeze solid on the spot.
The first step in the ice-gathering is to draw two long, straight lines on the ice at right angles to each other. With these as a guide, a part of the field is marked off into blocks of the proper size, and it then looks like a gigantic checker-board. Then other teams come on, drawing the ice-plows, which are long, narrow-toothed blades, run- ning along the ice like great horizontal saws. One plow follows another along these narrow grooves until they are deep enough, so that long strips of the outlined cakes may be readily loosened by a saw. These separated strips of ice grooved off into cakes are pushed along in a channel which has been cleared through the ice up to the foot of the endless chain that runs up an incline to the houses. Here the strips are broken apart along the deep cross-grooves into cakes by hand-bars shaped like great chisels. The cakes are now caught upon projections from the elevating chain, moved by steam, and up they go one after another to the platforms at varying heights around the ice- houses, or directly in at the main door. When the cakes enter the storage-rooms they are shoved along wooden ri;ns or movable tracks to various parts of the chamber where layer by layer they are stowed away. Sometimes a single inclined plane with its endless chain leads up to a series of platforms along the front of the building, which tier above tier slope gently away from the top of the incline, so that the ice-cakes, leaving the chain at the center, are slid down the platforms
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to the various openings. The ice-mass, which is quite imposing as one looks across it in the larger houses, must be carefully and skillfully packed, and be self-supporting. Many a dealer has come to grief by the fall of his building from the collapse of the ice-mass within. The construction of the great and elaborate ice palaces with which the people of Montreal and St. Paul sometimes amuse themselves in winter is comparatively simple, because water is jjoured in between the blocks, and the whole freezes to a solid mass as it rises. But the art of the commercial ice-builder consists in making his ice-mass solid enough to stand alone with just as little freezing together of the cakes as possible.
The more responsible harvesters are particular about the appear- ance of the ice which, is stored, and if a block is dirty from inclosed sand, grass, weeds, etc., it has to be thrown away. That sounds very simple, to throw away a cake of ice. But if one fancies that, in doing it, the offending object is dragged bodily off by hand out of the way, he underrates the value of machinery, gravity, and American enter- prise. No, the offending block is floated on toward the elevator along with the rest, and goes up in line like any reputable sheep. But its Nemesis awaits it at the top in the person of a man with a spiked stick, with which he unceremoniously bounces it off the end of the platform into a heap of broken ice below by one quick, skillful thrust.
Too much ice must not be grooved out by the plows in advance, lest in case of rain the channels should fill and freeze solid and the labor be wasted. So it is frequently necessary for the workers at the plow to be out long before light in the morning, grooving out blocks for the harvesters when the day begins. It is a picturesque sight, these hardy men, muffled to their ears, following the gingerly-treading teams back and forth over the ice-fields by the light of flaring, smoky torches hung on poles stuck in the ice. More than once the swinging lamps which have done patriotic duty in some campaign torch-light procession have found themselves relegated to the austere and chilling duty of illuminating hoary ice-fields before the dawn, instead of lend- ing force to the political claims and convictions of would-be or would- continue-to-be American statesmen after dark.
Serious accidents are not frequent upon the ice-fields, but occasion- ally a horse breaks through or slips off into the icy water, and has to be hauled out with ropes. The men, too, frequently enough, get an unexpected bath amid the jeers of their fellows. A change of cloth- ing and a stiff horn of whisky are the not unwillingly endured penal- ties which such an awkwardness entails.
At Highland Lake, which lies in the hollow of a natural rocky ter- race a short distance back from and above the Hudson below West Point, no power other than that of gravity is used in carrying the ice to the houses some distance away. A wooden runway leads from the edge of the lake down the hill. Down this the ice-cakes glide one after another as they are fed in directly from the water-level above.
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When the cakes approach the storage-houses they enter the top of a great wooden tower, in which the runways form a huge spiral. Dov/n this they slide with diminished velocity, and may be switched off at any desired level directly into the houses.
In good seasons a considerable quantity of ice is usually "stacked" ; that is, piled up in great heaps outside of the houses and covered up with hay or straw. This ice is shipped early in the season, and the housed stock saved for later use. Sometimes a considerable quantity of ice is carried over from one year to another, and serves as an insur- ance asrainst bad seasons. When winter is coming on and naviofation liable to close on the river, all the available boats and barges are filled with ice and sent down stream, and from this stock the early winter deliveries are made. When this is exhausted, the supply may be drawn from the houses which are in communication with the city by rail, or the ice may be cut near these houses, put into the cars, and forwarded directly.
The insurance of ice-houses against fire, and in many regions against wind, is an important matter. For, singularly enough, the destruction of these buildings by fire is of such frequent occurrence that the insur- ance rates are quite high. They seem to be favorite playthings of the lightning, and it is probable that the shelter which the lee and sunny sides of these large and often isolated structures afford to that most disgusting combination of man, brute, and devil, the modern tramp, would account for a considerable number of ice-house fires.
The ice used in Xew York is largely brought to town in barges or canal-boats, though a considerable quantit}^, notably that called Croton Lake ice, from Ice Pond and Tuckahoe, comes in by rail. The ice- barge, so familiar an object upon the river, is a singular, awkward craft, with a great square house upon the deck, with slender derricks in line fore and aft, and a small windmill at one end for pumping out the water as it accumulates from the melting of the ice. The New York ice-dealers are greatly favored by the extensive water-front of the city, which enables them to almost entirely dispense with expen- sive storehouses in town, the ice being for the most part loaded from the barges directly into the delivery-wagons.
The delivery of ice in Xew York is largely controlled by the com- panies which harvest it, by whom drivers are employed to supply their customers. There are other concerns which make contracts for ice on the large scale from the haiwesters, and sell and deliver to their own customers. But there is still a large number of men called " bush- whackers " and " guerrillas," who work up custom in various sections of the town, and get their ice where they can from the regular dealers.
We^re all familiar with the appearance of the ice-wagon, heavy and usiially clumsily built, a slight tilt of the body forward, painted with any of the colors of the rainbow, or more commonly with colors which the rainbow would blush to acknowledge, and adorned with
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some more or less attractive name. The name on tlie ice-wagon, often apparently indicating the source of the ice, may or may not actually do so. A large part of our ice comes from the Hudson River, and, as a rule, whenever and wherever Hudson River ice is more conveniently and cheaply delivered than that from any other source, this is what the consumer gets, no matter what the flaring legend of the cart may seem to imply.
Except the grocer, who visits us in guises as varied as are the wares which he dispenses, the ice-man is that one of the outside ministrants to our wants with whose appearance we are most familiar. Few escape hearing the infernal clatter of the ash and garbage carts, which, under the new regime, leave a trail of murdered sleep behind them in the early morning, or the uncanny whoop and screech of the milk-dispens- er. But they do not form such constant features of the street-life as do the ice-carts and their officers after the world gets fairly astir. We have all watched with interest the skill with which the experienced ice-man cracks off his larger and smaller rectangular blocks, and the ingenuity which he exhibits, when it is not carried in-doors, in select- ing a sunny place for its deposition on the steps. The never-failing attraction of the ice-cart for peripatetic children is the occasion of many picturesque street scenes, and not infrequently of serious acci- dents, for every now and then an ice-block falls off behind, and woe to the youngster who happens to be in its way, for ice weighs about fifty-eight pounds to the cubic foot.
There is yet another phase in the story of the ice which we must not overlook. We have been wont to believe that the fragment of ice which forms such a constant and pleasing adjunct to our glass of water is the very ideal of purity. But the common belief that, in freezing, water purifies itself from all kinds of contamination, has been shown to be quite untrue ; and, ungraceful as is the task of dispelling so pleasing an illusion, we shall do unwisely if we ignore the revelations of modern science, and for the sake of a momentary mental quietude remain oblivious to a real danger w'hich the indiscriminate use of ice for drinking purposes unquestionably entails.
Nearly all natural water contains considerable numbers of tiny vegetable organisms called bacteria. So small are they, for the most part, that thousands upon thousands of them, if ranged side by side, would scarcely reach across the head of a pin. Most of them are not only, so far as we know, entirely harmless when taken into the system in moderate quantities, but they are among the most important factors contributing to the cleanliness and continued salubrity of our surround- ings. Wherever under ordinary conditions a bit of organic matter, animal or vegetable, dies, these tiny structures appear and tear it to pieces, atom by atom, using a very small proportion as food, and fur- nishing the remainder in suitable innocuous form for the nutrition of animals and other plants in turn. There seems to be at first something
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repellent in the thought that we are liable to unwittingly consume, in our drinking-water, as we do in much of our uncooked food, such num- bers of living things. But this feeling is largely due to the wholly un- justifiable disposition "which many persons display to class them among " bugs " and " worms." Nobody thinks of considering the consump- tion of fresh fruits and vegetables as anything uncanny. And yet all the vegetables and fruits which we commonly use as foods are really made up of vast aggregates of tiny living organisms called cells, each one of which is the analogue of the single organisms called bacteria, and under ordinary conditions one is just as little harmful as the other. The leaves and fruits of some plants are exceedingly poisonous, and yet he who should on that account decline to eat lettuce or peaches would be justly reckoned among Nature's weaklings. The air v/e breathe in inhabited regions always contains considerable numbers of bactei-ia, but they are for the most part harmless.
We have learned a great deal about these, our invisible friends the bacteria, within the past few years ; and as that knowledge has grown, we have found out that lurking among them are a few species, not friends but our most inveterate foes, producing disease and even death. The fact is that, under ordinary favorable sanitary conditions, the bac- teria which we are liable to breathe or consume are as harmless as so much air. But if we insist upon drinking dirty water or breathing filthy air, we increase, as we deserve to do, our risk of coming under the influence of the baneful forms.
There are a few diseases common among us, the most important of which are consumption and typhoid fever, which are caused by the presence and action in the body of certain well-defined and well-known species of bacteria. These diseases never occur except under the in- fluence of these particular forms of germs. And the reason why con- sumption and typhoid fever continually occur is because certain of us get some of these bacteria in the living condition into our bodies, where they grow and induce the disease. All persons are not alike susceptible to the action of these bacteria, naturally or at all times, so that they doubtless not infrequently gain access to our bodies without producing ill effects. Now every intelligent person knows, or ought to know, that water polluted with sewage is not a proper thing to drink ; and, while there may be other causes which render it unwhole- some, the cause which we know most about is the presence of certain forms of disease-producing bacteria. This knowledge it is which has led to the construction for large towns of expensive systems of water- supply, whose reservoirs are situated at considerable distances, where, presumably, no sewage contamination is possible. If we can be certain that the water from our city supplies can not contain sewage or human or animal excretions of any kind, we are pretty safe, so far as our pres- ent knowledge goes, in giving ourselves little concern about the num- ber of bacteria which it may contain.
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But let us return to our ice. He who is familiar with the researches of Tyndall and other physicists on the structure of ice, knows how little we can be aware, from the simple inspection of a lump of clear ice, beautiful as it is, how marvelously it is built up crj^stal by crystal into the solid form we know so well. But if we turn a beam of sun- light upon it, concentrated by a lens, the exquisite and varied steltate figures which flash out within the solid mass as the magic touch of the sunbeam releases the molecules of water from their crystal bonds, give us enchanting glimpses of the still but half-won secrets of beauty and of order with which Natiu'e so fondly sports and still so cleverly conceals.
But the resources of the physicist do not suffice to conjure all its secrets from a block of ice. It is left for the student of that phase of Nature which we call life to discover that this very type of cold impassive lifelessness may be fairly teeming, absolutely transparent though it be, with whole families and races of living things — dormant from chill it is true, but ready at the touch of warmth, and in the presence of their food, to start on a career of growth and multiplica- tion to which the increase in the world's populousness since the old Ice age faded is but a poor and halting comparison.
We can not follow the student of these lowly forms of life, which have become entangled among the ice-crystals, as he calls them back from their torpor, separates them one by one, and patiently studies their life-history. It is not enough to melt the ice and look at the resulting water through the mici'oscope. But he mingles the melted ice with a transparent compound of gelatin and beef-tea, and puts the whole in a warm place, and after a few hours or days, wherever in this semi-solid gelatin a living germ from the ice had lain, a tiny speck or rounded mass appears — a " colony " he calls it — which is made up of thousands of the descendants of the old rescued and thawed bacterial ancestor. And so the biologist can separate the speties one from another, cultivate them in various receptacles, and learn whether they belong among man's friends or foes.
A great deal of careful experiment has shown * that water in freez- ing largely expels its coarser visible contaminations, and also that a large proportion of the invisible bacteria which it contains may be destroyed, even as many as ninety per cent. But still large numbers may remain alive, for many species are quite invulnerable to the action of cold. It has been found that in ice formed from water containing many bacteria, such as water with sewage contamination, the snow-ice almost invariably contains many more living bacteria than the more solid, transparent part ; so that the snow layer should be especially avoided in ice obtained from questionable sources.
Unfortiinately, the bacteria which cause typhoid fever are not readily killed by cold, and may remain alive for months, fast frozen in
- See the New York " Medical Record," March 26 and April 2, 1887.
�� � 68o THE POPULAR SCIENCE MONTHLY.
a block of ice. But the typhoid-fever germ can be present in water, so far as we know, only when it is contaminated with refuse from persons suffering from the disease ; so that, if we can be certain that our ice was cut from water uncontaminated with sewage or human waste, we have nothing to fear from its use so far as this disease is con- cerned. All of the pond and lake ice supplied to Kew York is of fairly good, and most of it of excellent quality ; and no doubt the danger of contracting typhoid fever from the use of the larger part of the Hudson River ice is quite remote. But a considerable quantity of the Hudson River ice is cut just below Albany, where the stream is so greatly contaminated with the sewage of two large towns, Troy and Albany, as to be absolutely filthy. In both of these towns typhoid fever is of frequent occurrence during the period in which ice is form- ing, and the waste from the victims passes directly into the river. There would, therefore, seem to be a very real danger in the use of some of the Hudson River ice.
The responses which one commonly meets when he has occasion to point out the possibility of danger from the use of impure ice are apt to be, " How horrid ! Why do you add another misery to life ? " or " Our fathers have never suffered from the use of ice, and why should we ? etc. No sanitary danger has ever been pointed out, and no improve- ment instituted, which had not to stem just such opposition. The cesspool has given way to the sewer, and the Avell to the distant water- supply, in the face of the same sort of silly protest on the part of many of those whose own most vital interests were at stake — persons who ignore the fact that an ever-increasing vigilance is necessary to ward off the dangers which the aggregation of large numbers of people in cities invariably entails. The danger from the use of impure ice in New York, though wide-spread, is not very alarming, so far as the liability to extensive outbreaks of typhoid fever are concerned, because most of the ice which is furnished appears to be of fair quality. But if the risk of an attack of the disease can be warded off from one in ten thousand of our fellows, the gain is worth the effort. We do not need to be unduly squeamish, but it is well enough to be intelligent in the face of sanitary dangers. The ice companies, unless controlled by the State Health Department, will doubtless continue to cut and to furnish sewage ice along with the rest just as long as their customers will tolerate it. But if householders would insist upon the assurance that their ice should not come from the immediate vicinity of Albany, or from directly below other towns draining into the river, the com- panies would soon recognize that acquiescence in this reasonable demand is the wiser and more profitable course.
We are a long-suffering people here in New York, and, if our com- mon manifestations of patience were commendable instead of con- temptible, we should be deserving of monumental record. We are, it is true, saved in a measure from swill-milk, bob-veal, and numerous
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other abominations, by the vigilance of our health-officers. But we smilingly swallow the dirt which the horse-car companies order thrown upon our streets to save themselves the expense of roughening the roadway in a legitimate manner ; we allow the elevated railroads to rain dust and cinders down into our eyes, and drop oil and water upon our heads and shoulders ; we stumble over boxes and baskets stored upon our sidewalks ; we permit political tricksters to juggle with our lives, even with Asiatic cholera staring us in the face ; we breathe, in some of our most popular, expensive, and fashionable theatres, air which, from lack of adequate ventilation, rivals that of crowded tene- ments and the steerage of stuffy steamships ; and in innumerable other ways ai-e the victims of the money-making and money-saving instincts of our fellows. But, after all, the complacency with which we swallow the frozen filth which some of the ice companies at times deliver at our doors — albeit often very clear and harmless in appearance — because it is cheaper for them to harvest it where the sewers empty than else- where, affords a spectacle of self-abasement as melancholy as it is dis- gusting. If the householder be not brave enough to encounter the scorn of the ice-dealer, or is too tender-hearted to witness the picture of injured innocence which he often presents when the details of his business are called in question, the ice which is used for drinking pur- poses may be put in a separate receptacle, so as not to come directly in contact with the water.
Our space does not permit us to consider the growing importance of the manufacture of artificial ice. But it seems probable that the sanitary problems which the use of natural ice for drinking purposes presents, especially in large cities, may find their solution in the increas- ing employment of artificial ice made from distilled or otherwise puri- fied water.
And now, at last, as we look at the old Ice age and the new to- gether, we find that, while in some respects alike, they differ widely in their significance and in their relationship to man. The mysteries of the old ice-crystals perished with them ; the grandeur of the great glaciers passed unseen, leaving desolation. What hardy germs were caught up by the ice as the last cold period came on, and were swept from one part of the continent to another, we can only conjecture.
The new Ice era came in response to the intelligence and the growing refinement of the material needs of man. Petty as it is in its physical proportions, when set in fancy beside the old, it over- tops it in significance, because it owes its very existence to the com- fort and healing which we compel it to bear. Our blocks of ice can to-day be made to yield up their secrets of marvelous physical consti- tution, and we can i-ead out of their inmost recesses the dainty records of the elemental warfare which silently went on, as now heat and now cold was victor in the water where it slowly formed. We can nurse back to life the delicate organisms which were sporting in the water
�� � when it fell under the spell of Winter's wand, and wring from them one by one the secret of their relationship to man — framing the pass-words by which we are to know whether they belong among his friends or foes. The use of ice should, and doubtless will, become more and more universal and liberal as time goes on, and we may unreservedly hail as a triumph of enterprise and skill, and a cherished factor in the advancement of man's weal, the advent and growth of our New Age of Ice.