EFFECT OF MANURES OF CROPS.

Waikato Times, Volume XVIII, Issue 1500, 14 February 1882, Page 3

EFFECT OF MANURES OF CROPS.

Yiar by year the work done in experimental agriculture increases rapidly, and the results obtained, which generally refer to the effects of manures on certain crops, are published in the monthly and weekly periodicals. But part of this work, over which much trouble and time has been expended, is in a great measure lost to the agriculturist ; for soils, climates, and local conditions varying greatly if the experiments are repeated exactly, disappointment follows, and labour and money are lost. It is therefore necessary, in order that the experimental results obtained by others may be made use of, that the modifications in the original plan which ought to bo introduced, and which are determined by the locality, should be discovered by independent experiment in each district. We not despair of the discovery in the future of some plan whereby agriculture will be regulated by rules other than those of thumb and chance. ■ It i? not proposed to enter here into an account of the various disturbing influences which rendered the modifications referred to necessary, but rather to lay before our readers a few facts, which may simplify their labour should they at any time venture to repeat on their own land the experiments of others. What we are about to say is rendered all the more necessary by reason of the method so frequently adopted in the descriptions of experiments as to the amount of manures employed. We read that 421b of phosphoric acid, or that 3cwt of superphosphate were applied per acre. AYe doubt very much if these statements produce any definite impression on the minds of many who have read such a report. How are they to discover the number of pounds of phosphoric acid in a " super ?" or will 3c\vt of some super which they have bought be as good as that which is described in the experiments ? It is an answer to these questions which we now give. Of course, if we are told that so many shillings' worth of 22 per cent superphosphate have been used, there is then no difficulty in doing likewise ; the difficulty to be overcome is when we ai-e told to use as much of a manure as shall contain a certain weight of some one constituent. In superphosphates, phosphoric acid, as is well known, exists in two forms, as the soluble and the insoluble phosphate of lime. The analysis, a copy of which can generally be obtained at the time of sale, states (1) the percentage of •'soluble or dissolved phosphate," by which is to be understood the amount of insoluble phosphate, or bone earth, rendered soluble in the process of manufacture. A second entry (2), which is explanatoiy of the first, is sometimes made, which states the actual amount of phosphate of lime (chemically termed monocalcium phosphate)whichissolublein water, and its porcentageisalwayslowerthanthat of the first. One more entry (3) may be found, namely, the percentage of insoluble phosphate of lime, or that part of the original material which has escaped alteration during the manufacture. To calculate, then, the amount per 1001b of the super of phosphoric acid contained in either 1 or 3, it is only necessary to multiply the percentages by 046 ; in 2, the amount is found by multiplying by 0607. The products from 1 and 2 will be the same, as the two substances are identical, the first being a technical term, the second the chemical term. Care must therefore be taken that both figures arc not employed in the calculation. As an example we quote the following analysis : Per cent. 1. "Soluble phosphate " (equal to bone earth made soluble) .. ... .. 21*84 2. Soluble phosphate, monocalcium phosphate 16*39 3. Insoluble phosphate S's& Multiplying the percentages of 1 and 3 by 0.4(>, we hnd that 1 contains 1011) and 3 contains 2\lb of phosphoric acid, though not in the same .state of combination. If 2 ba multiplied by 0*607, the same result iri obtained as when 1 is multiplied by 0.46. Of course, if the manure be v holly insoluble, as in the case of bones, there can be no doubt as to which factor to employ. Nitrogenous manures being also largely employed, either as sulphate of ammonia, nitrate of soda, or raw bones, it is necessary to show how it is possible to translate a given number of pounds of nitrogen /into sulphate of ammonia, &c, or vice vena. The analyses state, besides the phosphate of lime, the percentage of ammonia which can be obtained from the bones. To calciilate the amount of nitrogen to which this percent ige is equivalent, divide by 1*214 ; or, supposing that it is desired to know how much pure sulphate of ammonia will contain the same weight of ammonia, then the ammonia in the bones must be multiplied by 3*BB, and its equivalent in pure nitrate of soda will also be obtained by employing the multiplier 5. In the same way we may calculate the quantities of guano which are equivalent to known weight 9 of sulphate of ammonia, &c. The only other manure to which we need sppcially refer is kainit, which contains at least 24 per cent of sulphate of potash. Multiplication of the percentage of the sulphate by 0*44 gives the amount of potash present. By the aid of these figures we hope that some of our readers will be able to understand, and to appreciate more thoroughly, the experiments which have been carried on for years past by such earnest workers as Messrs Lawes and Gilbert, and others.

Ik we are told that a man is religions, we still ask, " What are his morals ?" But if we hear at first that he has honest morals and is a man of natural justice and good temper, we seldom think of the other que&tion whether he be religious and devout. The entire area of Australia and Tasmania contains 2,970, 394 square miles of land, which, taken as representing 100, the respective areas of the colonies show the following percentage of territory :—: — Victoria, 2*92 ; New South Wales, 10*40 ; South Australia, 30*41 ; Queensland, 22 47 ; West Australia, 32.83 ; and Tasmania, o*Bo. The Fikst Fellow She'd Had. — 'Twos a dull, heavy evening ; the light of the dozen gas jets along the street only served to make the haze and fog visible. The clock thus tinkled forth the hour of nine, and with the usual remark that " 'twas time honest folks were abed," old McGunnigiggle trudged on upstairs, followed by the aged partner of his sorrows and searcher for his joys. " Don't you young folks sit up till the morning paper comes, this time, "shouted £ghe over the banister. "Nb-o-o," replied a sweet voice from the parlor ; " we won't, will we," eaid she ill an undertone. "Not if I know it," was the reply. "If the old folks are going to be as sour as this, I guess I'll ship now," and he reached for his hat. "See here !" and the girl's eyes gleamed with earnestness; "you're the first fellow I've had, and you've got to put down that hat and sit up and court me in good shape. I'm homely, I know, but I can build better bread, iron a, bosom shirt J)andsom'er, knit a pair of stockings 'ijuicker, and make one dollar, thirtyseven cents go further than any girl in J;h'6w. village. .Them's any recommendations. "That wits me exactly," and %is hat flew into a corner, and that evening- the details of the wedding were all afranged. He depended on a , girl as smart as that to get the best Qf - ttie old