No. III.] EXPERIMENTS ON EARLY POTATOES. 21 • 



a very well digested and well drawn up paper, detailing numerous experiments 

 made by himself during the past summer. Among these is one upon the use of 

 this same mixture upon thepotatoe crop, which I shall quote in his own words: 



" April 26th. — Planted potatoes of the red Don variety, soil a mellow loam, 

 two feet deep, subsoil yellow till. Farm-yard dung was trenched in some days 

 before planting, at the rate of 40 cubic yards per acre ; sets drilled in with the 

 hoe. Plants came up very regular, and were top-dressed with a mixture of | 

 sulphate and J nitrate of soda on June 2nd, at the rate of 2 cwt. per acre. They 

 grew very strong after this application. Stems six or seven feet in length, dark 

 green, and the produce, when lifted in October, was 16 Renfrewshire pecks of 35 

 lbs. each per Scotch fall of potatoes fit for market." 



This produce is equal, 1 believe, to about 26 tons per Scotch, or 21 tons per 

 imperial acre, about equal to that of Mr. Fleming with the same mixture. And 

 what an amazing luxuriance of vegetation, to yield at once stems seven feet in 

 length and upwards of 20 tons of tubers per acre ! 



Those who are the most sceptical in regard to the benefits to be derived from 

 agricultural experiments, when well conducted, will scarcely question the impor- 

 tance of this result — the most backward in making experiments will be anxious 

 to repeat this upon his own potatoes. The cost of the mixture to be applied in 

 the quantity used by Mr. Fleming is as follows : — 



S„,pha.eofSoda | ,g ^s'. St^'e^Js'l^arsr." | « ^ 

 Nitrate of Soda . . 75 lbs. at 22s 14 9 



21 6 



The return for this 21s, 6d. was in each of the above cases upwards of 8 tons 

 of potatoes. 



I may here mention also two other interesting experiments of Mr. Gardiner, 

 in which he tried the effect of sal-ammoniac upon his potatoe crop, — 



1°. In the one he mixed sal-ammoniac, previously dissolved in water, in the 

 proportion of 1 lb. to each cubic yard of a compost formed from the refuse of the 

 garden, and planted early potatoes with it at the rate of 35 cubic yards per acre. 

 The produce was one-sixth more than when no ammonia was used. The va- 

 riety of potatoe was Taylor's forty-fold, the soil moss and clay. The cost of 

 this application was 19s. per acre. 



2°. Sal-ammoniac, dissolved in water, was sprinkled on moss or peat earth, 

 at the rate of 20 lbs. to a ton of earth, and, after strewing a little lime at the bot- 

 tom of the drills, this mixture was put in at. the rate of 2 tons per acre. The po- 

 tatoes were 14 days later in coming through the ground than the same variety 

 planted with farm-yard manure. They were strong in the stem, of a dark green 

 colour, and equal, in point of produce, to the others. The variety of potatoe 

 was the Irish apple, the soil a very light brown loam, of that description locally 

 named deaf 



I may observe on this latter experiment, that the application is not so simple 

 as it appears. The lime would decompose the sal-ammoniac, and form chloride 

 of cakiiini, while ammonia would be liberated. The effect, therefore, may be 

 partially due to both. It will be recollected that in a previous part of this Ap- 

 pendix I suggested the trial of this chloride of calcium as a top-dressing for va- 

 rious crops. 



5. — Experiments on Moss Oats, soion about \st May, 1841, top-dressed Slhth June. 

 *' These top-dressings were applied on the 5th of June, and by the 24th there 

 was a striking improvement, especially on No. 2 and No. 7. It was quite visi- 

 ble in greater strength and evenness of crop. One or two of the others also 

 showed improvement, but not so visibly as to merit particular notice. I exam- 

 ined them from time to time, and at different dates : the appearances much the 

 same as noticed upon June 24th. I again examined them a fev days before 



