This Society is doing a good work by its conversational meetings. The discussions thus far possess so much interest that we gladly make room for them, and hope they may be continued. The names of the officers we present elsewhere. The subject for discussion at the last meeting was Manures, and the following instructive essay was read by Prof. L. Stephens of Girard College.

The term manure is applied to all those substances which enrich the soil in those elements which contribute to support vegetation, and may perhaps with propriety, in a wider sense, apply also to those chemical agents which seem to liberate and render available to plants those fertilising elements which already exist in the soil, but locked up in a state of insolubility, and may also embrace those substances whose application to particular soils improves their physical texture in such a way as to enable a crop to obtain abundant sustenance.

The organized tissues of all plants consist chiefly of four elements, three of which, in their free or uncombined state, are gaseous bodies viz., oxygen, hydrogen, and nitrogen, and the fourth, carbon, although in its simple state a solid, still in its union with oxygen forms a gaseous compound, carbonic acid, which is universally diffused, in the atmosphere, the water, and the soil All of these elements, either as gaseous or liquid compounds, are universally diffused, and without the aid of man sustain the luxuriant growth of our forests and our prairies. Of these elements, three, oxygen, hydrogen, and carbon, constitute the vegetable tissue, or the entire framework of the plant, while nitrogen is invariably contained as an essential element in the seed, and appears to be indispensable to all vital action in the plant; for it is found not only in the seed, but in the cells of every growing part of the organism, as one of the constituents of that viscid liquid which lines the inner wall of the cell, and from which new cells derive their birth.

But besides these organic elements, there are found certain mineral constituents in the sap and cells of every plant, which are indispensable to its growth, strength, and health. These are potash, soda, lime, magnesia, oxide of iron, silica, phosphoric acid, sulphuric acid, and muriatic acid. While of the organic elements plants derive a large part of their supply from the water and the air, their mineral constituents must be derived wholly from the soil. Different crops require of these minerals different quantities and in different proportions. Thus, clover and'pens require a much larger amount of lime and less silica than grass or grain. And potatoes and beets require more potash and less sulphuric acid than turnips. Chemical analysis has fully proved that within a certain narrow range of variation, each crop must obtain from the soil its own particular proportion of these mineral constituents, and that the absence or the deficiency of any one of them will cause a failure of the crop. In the absence of manuring a cultivated field, the crops must derive their inorganic constituents from the natural disintegration and decay of the mineral of the soil by which they are brought into a state of solubility.

These minerals are removed from the field with each successive crop, and in a limited period, longer or shorter, barrenness is sure to follow.

We come now to the question, What is the best manure to sustain the fertility of the soil? I answer, that for general application farm-yard manure must take the first rank as a fertilizer containing all the substances required to sustain vegetation. An artificial compound may be made to have the same fertilizing power as barn-yard manure, but, in order to do that, no one of its constituents must be lacking. Although the manufacturer may intensify the fertilizing power of his compound by concentration, he can not for general use improve the proportions of the ingredients of barn manure. The excellence of barn manure consists, of course, in the fact that, being derived from the varied food of domestic animals, it contains all the mineral elements which vegetation extracts from the soil, together with a good proportion of carbon and nitrogen. Moreover, the processes of animal digestion and secretion have again in a measure brought these mineral matters which had become fixed in the plant into a soluble state, and therefore again ready to contribute to vegetable nutrition. In this point of view it is evident that this manure must include both the liquid and the solid excrements.

In fact, of the two, the liquid excrements are the most valuable, on account of the large amount of nitrogen contained and the entire solubility, though neither of the above constitutes a complete manure.

But although barn manure may be considered a complete manure from the fact that its continued application will sustain the fertility of a soil, still the degree of fertilization can be profitably increased by the additional use of animal manures from time to time. Flesh, blood, hair, bone, etc, are formed chiefly from those vegetable elements existing in the seeds and nutritious roots of plants; they are consequently by far richer in nitrogen, phosphoric acid, and sulphur, the distinctive elements of seeds, than is that part of the food of animals which is rejected in the form of excrements; and which, on the other hand, is richer in some of the mineral elements derived by the plants from the soil. To make, therefore, the animal manure a complete manure, it is only necessary to add to it those mineral matters in which it is deficient. Of all the fertilizing elements contained in manures, by far the most expensive and valuable is nitrogen, whether in the form of salts of ammonia or of nitric acid. The next most valuable ingredient is phosphoric acid, and the third in order is potash.

If we estimate the relative efficacy of farm-yard manure and animal matter merely by the amount of nitrogen contained in them, we have the following scale of values according to Johnson:

It must also be borne in mind that these animal substances are much richer in phosphoric acid than barn manure, and that wool, hair, and horn contain about five per cent, of sulphur, which answer valuable purposes in the nutrition of plants.

(To be continued).

Progressive Gardener's Society #1

This Society still continues its interesting discussions, for a copy of which we are indebted to the Secretary, B. Robinson Scott, who will please accept our thanks.

I will now tell you bow I have seen manures composted in Edinburgh, when I was a lad. A man had a large yard back of the castle, with a canal through it, divided into three compartments by sluices; the aides was stone-walled and flag-bottomed; alongside the yard were slaughter-houses, tanneries, and currier shops; the offal and washing of these places were thrown into the canal and mixed with stable manure hauled from the city, and after lying a fortnight, being flooded all that time, the liquid was let off into another compartment, and the manure thrown out into a heap, well mixed, and after becoming well fermented it was made into heaps a yard high, and as long and broad as was engaged for. It was always bespoken before it was made up, and sold by the square yard. The great quantity of tan-bark among it neutralized the bad effluvia; it produced heavy crops of all kinds. An after compost was made by farmers near the city, who paid a high price for the contents of the water closets. The night soil was collected and emptied nightly, and hauled out to the farms, and put into large basins made with road earth; a single horse load of coal ashes from the city was put above a double horse load of manure as a deodorizer.

After the basins were full they stood so a month; then the road earth forming the sides was cut up fine and thrown on top, and the whole turned over and mixed, and in a fortnight more it was applied to the land, and made early and heavy crops. Another compost was made with the roots of perennial weeds gathered off the field after being plowed and harrowed, and cleanings of ditches mixed with stone lime; the slacking of the lime burned the whole into a mould, and after being turned and well mixed, it was hauled out and spread upon the lands, and produced good crops. Sometimes a heap would have three hundred cart loads. Another compost was made with road earth, lime, and tan-bark, turned and well mixed twice, and never used until a year old; it made good crops.

Liquid Manure are the essence of the solid manures, generally speaking; they give more immediate effect to plants and are well suited for pot-culture, and I think that they are better for woody plants than solid manures, and they can only be taken up by them in that form; they incorporate at once with the soil. Fruit-trees, gooseberries, currants, raspberries, are particularly benefited by them, but they should be applied immediately after rains during hot weather, or be very weak. I think that they do moat good if applied in winter or spring. The liquid of the barn-yard is perhaps the best. Soapsuds appears to be of a burning nature, as it hardens the soil very much in hot weather.