276 Transactions of the Society 



entirely and completely out of view the opinions and conclusions of others, 

 some of which were favourable to the views I entertain. 



" The complete insolubility of coal-dust seems to be the insuperable objec- 

 tion to its utility as a manure ; but surely it is not more insoluble than the 

 effete ashes. 



" I am inclined to believe, from a long-continued series of observations, that 

 the slender filamentous radicles of plants have a power in all respects equal, 

 if not superior, to small electro-galvanic wires of low intensity, which, by 

 slow continued action, decompose most substances that are presented to 

 them, and, among others, that of coal-dust. Whatever the vital principle 

 may be, we cannot assign it a lower grade in the scale than that of electro- 

 galvanic influence ; and we are not assuming too much for the vital action of 

 the radicles when we claim for them a power equal only to that of small 

 galvanic wires, which can and do effect a decomposition of coal-dust. 



" A multitude of facts seem to confirm this idea ; but it is not my intention 

 to enter on this wide field, but simply to strengthen the proposition of coal- 

 dust for manure by fair and rational statements. It is certain that substances 

 regarded by us as nearly insoluble are absorbed into plants in large quantities. 

 I have taken great pains, on a small scale, to demonstrate the fact, that coal- 

 dust is not mimical to vegetation, by filling a series of garden-pots with fine 

 coal-dust, and planting and sowing a variety of plants therein, as potatoes, 

 onions, &c. &c. In all of them the vegetation was extremely vigorous and 

 luxuriant. I have filled hyacinth-glasses with coal-dust, and put bulbs 

 therein, supplying water as required ; and the result, when compared with 

 those without the coal-dust, was very marked and evident : large, healthy, 

 strong plants being produced, and admired by man}^ 



" I can only say, that those who will fill a box with coal-dust, and plant 

 potatoes therein, will obtain a good and early crop, more bountiful and finer 

 than when in common mould under similar circumstances. 



" Strawberries, onions, and a vast variety of useful and ornamental plants, 

 thrive extremely well indeed in coal-dust. 



" Coal-dust is remarkably clean and neat, inoffensive, without odour or 

 stain, not capable of harbouring insects or maggots, well adapted for in-door 

 floriculture, and enduring for a long period, not consolidating or becoming too 

 hard by frequent watering, and possessing many great advantages. 



" As coal-dust is so insoluble, it must of necessity be very slow and gradual 

 in its action, diffusing its influence over a long space of time, not coming into 

 action quickly ; and, independent of its insolubihty, it has very little power of 

 retaining moisture : hence, it is well adapted for those plants that like a light, 

 loose, dry, and sandy soil, with the evident advantage of containing a very 

 large amount of nutriment. Of course, coal-dust requires to be intimately 

 mixed with the lower portion of the soil where the radicles extend, and then 

 its beneficial action will be very perceptible on the crop of potatoes, peas, 

 turnips, or cabbages ; indeed, all evidence the fact of its being most useful. 

 I could detail many experiments most satisfactory, but leave the subject with 

 this communication, assuring your Society that truth, reason, and experience 

 attest the fact to be as I state ; and whoever will try it on a small scale, with 

 the knowledge of its being a slow and steady manure of no mean power, will 

 not be disappointed. 



" But those who may be indisposed to adopt the use of coal-dust, may be 

 induced to try a very excellent combination of coal tar and slacked lime. 



" One gallon of coal-tar, mixed up well and completely with one bushel of 

 slacked lime, produces a material of warmth and value as a manure; rich and 

 stimulating, and tending very much to keep away the flies when sprinkled 

 freely in and among the young turnips. 



" I have used this compound with excellent effect on peas and potatoes, 

 producing an evident and marked effect over the rows where none was used. 



" Animal tar, or dippel oil, procured from the distillation of bones, and at 

 present, I believe, a nuisance, if used with slacked lime in the same manner. 



