A TUNNEL OF MUSHROOMS.

Star (Christchurch), Issue 6126, 12 March 1898, Page 1

A TUNNEL OF MUSHROOMS.

(Pearson's Magazine.) Edinburgh is a city of charms and surprises. For example, within its boundaries you will find vegetation existing at a higher altitude than in any other city in the United Kingdom— namely, on Castle Hill, while under the very streets there flourishes a veritable market garden, owned by the Scottish Mushroom Company, in which are produced the finest mushrooms to be obtained in the world. This is the only known instance in which mushrooms are grown in a railway tunnel. Usually the mushroom farm consists of any old buildings — stables, granaries or barns — or they are cultivated in the open, covered over with a blanketing of canvas. Darkness is indispensable to the successful production of mushrooms, and no more suitable position could be imagined than a vast subterranean passage over 3000 ft long, absolutely light proof, for both ends are built up. Naturally, the tunnel was not originally constructed for the office it at present fulfils. It is now' more than fifty years since the North British Bailway Company built this line, which buries itself 60ft below the streets of Edinburgh, as a part of their Edinburgh, Perth and Dundee system. In itself it is a magnificent piece of engineering, and the only reason why it fell into disuse was the fact that the gradient of one foot in twenty-seven proved too heavy for the locomotives to draw up the trains without the assistance of an endless wire rope worked by a stationary engine at the north entrance. Another . line was therefore constructed which carried the traffic outside the city, and for over twenty years from that time this tunnel lay unused. In 1887, however, Messrs Eobert and John Paton, of Glasgow, conceived tho idea of utilising it for the purpose of cultivating mushrooms. After coming to an arrangement with the railway company, they bought up several hundred tons of soil and manure, built beds, planted mushroom spawn, and, after endless experiments as to the best way of producing the fungi, now have the satisfaction of practically CONTROLLING THE MARKET IN CULTIVATED MUSHROOMS. One tremendous advantage which this farm has over its rivals is the evenness of the temperature — a most important consideration in growing theso delicate fungi. It is the expense and trouble of endeavouring to preserve this condition of affairs on other farms which rely upon small buildings, that makes the cost of producing the mushroom in many cases prohibitive. Except when a prolonged frost occurs — in which case a fire is lighted at the mouth of the tunnel — the thermometer throughout the year varies only to the extent of about ten degrees. Moreover, to successfully produce the mushroom for the table, comparative cleanliness of surroundings is found to be advantageous. Consequently, in this particular instance, the walls and roof of the tunnel are whitewashed periodically, at a cost of J2300 on each occasion. An enormous amount of care must also be given to preparing the beds. Experience alone will educate a man as to the correct proportion of manure and soil to be used successfully. Boot reading is of no genuine utility except as A ROUGH GUIDE TO THE PRELIMINARIES. The beds may bo of any length that is convenient. In some instances they run to 30yds or 40yds, and to sft in width. The Scottish Mushroom Company, howevor, consider 12ft by 3ft the most convenient proportions. After tho bed has been built of soil and manure in the correct proportions, it lies unused for a few weeks until its temperature is reduced ; for, although mushrooms \ are ableto stand the cold, too much heat or moisture is fatal, especially to the delicate spawn, which would be burnt up by the natural heat of a newly made bed. In order to ascertain when the bed is in a proper condition for receiving the seed, a stick is pushed into the centre, and, by feeling the end of it when withdrawn, the foreman assured me ho could tell the exact temperature without the assistance of a thermometer. The spawn is prepared by firms who may not necessarily be mushroom growers themselves ; for, curiously' enough, although the mushroom will, if allowed to remain until the laminaj have turned black, produce multitudinous spores which fall from its gills, THE SPORES NEVER PRODUCE MUSHROOMS DIRECT. The true reproducing matter is found as masses of white, cobweb-like filaments in manure that has lain untouched for some time, and a small lump of the pure spawn is sometimes worth .£3 or .£4. This spawn— which, resembles nothing so much as mildew-is mixed with an earthy preparation and moulded into cakes about 9in long and sin wide, and about an nch thick, each of which is broken mtc .eight pieces and thrust into the *#**«£ under a congenial temperature thes pawn spreads rapidly and eventually produces.

tubercles which develop into mushrooms an operation which takes from three weeks to a month. It is a common belief that the wild specimen of mushroom becomes fully developed in a single night, hence the expression "mushroom growth." As a matter of fact, the length of time occupied in growing in the case of both wild and cultivated fungi is, all things being equal, exactly the same. / Occasionally, while you are standing in a field during a heavy rain, you will observe it gradually whitening as the masses of mushroom tops become visible, just as if the moisture had stimulated their growth, and that they had forced them- j selves up through the ground and become fully developed in the space of a few minutes. This, however, is not the case. The fact of the matter is that the rain, in falling, beats down the grass around the mushrooms and exposes them to view. In all there are 800 mushroom beds in the Scottish Mushroom Company's tunnel. They cover the whole of the floor, with tlio exception of the space occupied by a single set of metals along which run the trucks, which are always at work cither bringing in soil or carrying out baskets of mushrooms. So delicate and sensitive to the effect of foreign substances are the fungi, that the locomotive which enters their growing place is obliged to burn only smokeless coal, and to blow off steam as infrequently as possible. A cloud of smoke or steam coming in contact with the mushrooms WOULD KILIi OFF HUNDREDS OF THEM. When in full operation about one thousand tons of manure yearly are used, aud one thousand bushels of spawn. The highest output reaches about five thousand pounds of mushrooms a month. Naturally, amongst such a mass of fungi there appears an occasional monstrosity. One, for example, developed so rapidly in size that it measured twelve inches across the top before it was plucked. This is about the diameter of an ordinary straw hat. Mushrooms of this size, however, are not marketable, and so the proprietors would rather have a dozen small ones than another of these dimensions. Another oddity showed itself in the shape of three mushrooms growing one out of the top of the other, and a fourth was beginning to form when, on account of its top-heaviness, the parent fungus BROKE OFF AT THE STEM. "We are constantly in receipt of communications from all parts of the conntry asking our advice as to the best means to adopt to grow mushrooms." Mr John Paton told me; " but unless the applicants can secure conditions similar to those we have, they will inevitably fail, as many have done. Cryptogamists, and botanists generally, frequently come from all parts of the world to see our tunnel, and we have bad visits from members of the Royal Family. " Our facilities for sending to the leading markets are such that mushrooms gathered from our beds here in Edinburgh in the evening are delivered in London next morning in time for breakfast, and our local trade is of such a kind that any one can have mushrooms on their table, cooked, within an hour after they are cut." This steady aud continuous supply has created a demand for mushrooms which can only be compared with the universal demand for tomatoes. In the old days it was very uncertain if mushrooms would be found on the table, and the menu cards at restaurants seldom contained the word. Now, however, they are about as common as potatoes as an article of food, and this is not the result of foreign enterprise j for, whereas ten years ago the quantity of French mushrooms consumed in Great Britain largely exceeded those of home growth, they form at present only about one-hundredth part of the total supply.