196 



THE SOUTHERN PLANTER. 



broad bed (forty feet wide,) of well drained low- 

 ground. The adjoining beds on both sides, and all 

 the land, ploughed without sub-soiling. The land 

 planted in corn, and followed by wheat. No bene- 

 fit, from the sub-soil, on either crop. 



For the Southern Planter. 

 CARBONATE OF LIME IN MARL. 



Mr. Editor, — Mr. Gresham's article in the May 

 number of the Planter contained directions for as- 

 certaining the proportion of the carbonate of lime 

 in a given quantity of marl, which it is easy to 

 show would lead to very fallacious results in prac- 

 tice. It is a matter of no little importance to the 

 farmer who has the good fortune to own a " bank," 

 that he should be able, by some simple and easily 

 conducted process, to form a correct opinion of its 

 per centage of lime. It is a pity that Mr. Gresham's 

 mode of analysis can not be relied on, as' a neater 

 or more convenient one could hardly be suggested. 

 The analysis, predicated on the known relative pro- 

 portions between the lime and carbonic acid in the 

 carbonate of lime, would be almost perfectly use- 

 less, were the carbonic acid the only substance 

 evolved by the addition of muriatic acid to the 

 marl; but this is far from being the case; hence 

 the error of Mr. Gresham's deductions. Without 

 repeating here the directions given by Mr. G. I re- 

 fer the reader to his article — the loss sustained by 

 the hundred grains of marl, after being saturated 

 with dilute muriatic acid, is given as the measure 

 of the carbonic acid in the marl, then by a simple 

 formula, the quantity of the carbonate of lime in 

 the specimen is arrived at. 



When you add dilute muriatic acid to marl con- 

 taining a notable quantity of the carbonate of lime, 

 at least three gaseous substances begin immediately 

 to pass off: carbonic acid, watery vapor, and the 

 fumes of muriatic acid. Without being able to 

 ascertain precisely the volume of the two last, it 

 is presumed that combined, they are fully equal to 

 the carbonic acid lost. If you wish to prove the 

 rapid evolution of the acid, dip a feather in a phial 

 of aqua ammonia and hold it over the mixture 

 while effervescence is going on — the white vapor 

 of the muriate of ammonia is instantly seen. By 

 placing a piece of glass over the jar, the vapor of 

 water is soon deposited thereon. Soon after read- 

 ing Mr. Gresham's article, in order to test his mode 

 of analysis, I subjected a specimen of very poo. 

 marl to the test; this I had analyzed by other me- 

 thods repeatedly and knew that it contained some- 

 times as little as seven, and never more than ten 

 per cent. Mr. G.'s plan gave twenty-five per cent. ! 



I am sure that Mr. Gresham will sec the reason- 

 ableness of my objection to his analysis, and will 

 take it in good part. It is not to be expected that 

 farmers should be very accurate chemists, though 

 we may talk for the benefit of " the country mem- 

 bers " very learnedly of acids and alkalies ! The 

 writer of this stricture does not pretend to be very 

 profound himself, though chemistry is more in his 

 line than that of Mr. Gresham, who has not the 

 happiness of enjoying the uncommon honor of be- 

 ing a country doctor as well as a farmer. 



Mr. Gresham obtained his directions, it seems, 

 from the late lamented Dr. Braxton, whose noble 

 qualities as an intelligent, high toned gentleman, 

 and whose great worth as a farmer and citizen, it 

 would be oat of place to more than allude to here. 



But it is evident that in giving such directions for 

 the analysis, the Doctor had not submitted them 

 to the test of his own sagacious and practical scru- 

 tiny. I have seen the following simple method 

 practised by Dr. Braxton himself, and believe that of 

 all the approximate modes of analysis, it is by far 

 the most reliable : 



Weigh out one hundred grains of marl, previously 

 dried and pulverized, place it in a wedgwood mor- 

 tar or cup, and add dilute muriatic acid till effer- 

 vescence ceases. All the lime in the form of the 

 muriate of lime and the chloride of calcium re- 

 mains suspended in solution, and of course the 

 carbonic acid has passed off; then take a square 

 piece of filtering paper, and folding in a conical 

 form, make a filter, into which (placed in any con- 

 venient vessel,) pour the solid and liquid contents 

 of the mortar. Put it to one side, and let every 

 drop of the fluid percolate through the filtering 

 paper; then take the solid residuum, dry thorough- 

 ly, separate carefully from the paper, and weigh. 

 The difference between the weights before and after 

 using the acid, will give the farmer the quantity of 

 the carbonate of lime in his marl — at least suffi- 

 ciently near it for practical purposes. 



Wm. S. R. Brockknbrough, M. D. 



Westwood, Hanover county, May 27, 1854. 



For the Southern Planter. 

 A CHEAP PLANTATION GATE. 



Mr. Editor, — My vocation during the greater 

 part of my past life has subjected me to great in- 

 convenience, both by day and night, by ill contrived 

 plantation gates, gaps and drawbars. It may be 

 worth while to occupy a small portion of your co- 

 lumns with a description of a gate, the cheapest 

 and best which I have ever seen. It has the merit 

 of being so simple that any man who can drive a 

 nail, saw by a line, use a square, or a measuring 

 tod, and plant a post, can make it in less time and 

 with less skill than is necessary in fixing up a com- 

 mon pair of drawbars, which I consider to be a 

 common nuisance. 



But to the description of my gate. For the plan 

 of it I am somewhat indebted to one of the earliest 

 numbers of the Southern Planter, which is lost, 

 and the precise number not recollected. I have 

 made several modifications in the original plan, all 

 for the better. Say you want a gate five feet high and 

 seven and a half feet wide. Let your longinal slats 

 be eight feet long, four and a half or five inches 

 wide, and three-quarters of an inch thick. Your 

 upright pieces may be of the same sort of timber 

 in all respects, except that the pivot end of the 

 gate, upon my plan, requires at least seven feet in 

 length of its timber, whereas five feet will suffice 

 for the swinging end, which will be found to work 

 better by having its upright slats not more than 

 three inches wide. Each piece of the timbers being 

 precisely of the same thickness, will give to the 

 pivot end of the gate a substance of, say of five 

 inches in width, and two and a quarter in thickness, 

 which may be easily rounded off with a drawing- 

 knife, to suit your fancy or judgment about the 

 hinge machinery. Mine is exceedingly simple ; the 

 heel or pivot being rounded off, and say five or six 

 inches below the bottom slat, a foot or two above 

 the top slat — the pivot turning in a hole, bored or 

 gouged out for it, and the top so rounded as to work 

 in a hole, within which it may turn with ease, and 



