PROFESSOR BLACK AT CAMBRIDGE.

Waikato Times, Volume XXV, Issue 2103, 31 December 1885, Page 4

PROFESSOR BLACK AT CAMBRIDGE.

(Continued.) As to the waste of phosphato of lime in England, EngUnd had bt>en cultivating hei noil for the last thousand years. For the last five hundred yeirs theio hid ber>n a very considerable population, consuming considerable qu.vititi-s of fo >d. But think of what England hid lvon doing with the phosphate of htm which for .-ill thoso yeir■he had been o\ti acting from hor sml ' Take all tho world over and they .vould find that nearly all of tho great cities and town* wwro wither on the se» c >nt or on the bmks of mighty rivers, as if for tho express con vnnience of sending tho very wealth of their •oil into tho «o >. In this way tho phosphate win extracted from the land, and daily wasted, not only diminishing the wealth of the country, but absolutely and unnecessarily waiting the gmit naturil stimulants with which naturo had not too abundantly endowed us. All the shnep and cittle of Scotland and Ireland With their phospinto wore d Lifted into London and the other great atio-*, nnd in the usual course thoy pa*-, ou into the so i. SnpiMMing that England for the last him dred years hid not been importing gvuno and phosphato from fnieign countries, c mid it be mipposed for a minute th it sho conk' now be rinsing the large herds of cattle and ■heep and tho large crops of wheat, oats and other produce ? Not a bit of it. She would be almost as poor as Palestine, Even with the extraordinary quantities of artificial manures which she now imported, it took England all her tune on the best land m tho country to raise more than from 25 to 3") bu-hels an acre. They were simply growing crops on the manure they put in, and did thi*y not uso manure they would have no crops at nil. Th.it woo what England had come to. Thousands of ships laden with guano arrived every year in the ports of England. In addition to this there were the great f.wtoriej uheie artificial m inures were turned out in lar^e quantities And not only this, but England wus plundering Ne.v Zealand of her phosphate of lime. Every week, we in New Zealand continued to send away tho phosphate of our soil, in the laigc shipments of frozen beef and mutton. We robbed out paddocks hero of the great producing stimulant, and it went to London in the bones of our sheep, and from London it was passed down the Thames into tho sea. It might not mutter so much if the price which we got for out mutton, our beef, and our wheat enabled ua to replace the lost stimulant. But it did not. The price we got for our produce barely compensated h>for tho phosphite alone. Take Franc j for inntiince. This country has, hko England, bean raising crops with all her mi^ht snid tiding them in h> r own eomitiy, and hoi large cities were sending the veiy heart's blood of the country out to tho sea in their ■ewuge. They too, like England, spent vast sums of money in impoiting tint which, with inhniHy less cost, might be aaved from her sewage, and which was now ruthlessly wasted. Ona of two things mu*t happen. Either tho population must get scaice, or tno population being maintained in its piesent iiumbei^, they nvist all become nckotty tor want of their phosohato of lime. And, again, the people must grow less in m/o so as to have sufficient to maintain them. The population of France wpra not only diminishing in number, but also in statute. In the army they have had to lower the stature so a* to get recruits. The same rule applied to other countries, which 3,000 years ago wore most populous and wero at the present time almost denuded of their p filiation. But how was it that China, swarming with her 400 millions of people, still maintained her population? The Chino<o had not wasted their phosphate of lime. The sewage there was not thrown into the sea and wasted. It was returned to the soil from whence it camo, and tho fertility of the •oil was accordingly retained, and in this direction they could wf»ll claim to teach us h lesson worth learning. Wo looked upon the Chinese an a half barbarous and uncivilised people, and no doubt they wero in many respects but there were things in which wo were very m-ich less civilised than they were. In the case of K/ypt, which was also very populous and still very fertile, not because they imitated the Chinese in respect of the sewage, but the heavy rains and the melting of the miows that wash down tho mountain sides, gathering up the phosphate of lime and other valuable sub-ttanco*, and carry them down^o the Nile, causing the river to o\eifiow every year, and spreading it all o\or the country as a. -<i>i tof top dressing. The lecturer then referred fit some length to tho different qualities or classes of lnne, and th« different crops which required lime in greatest quantities. There liny bo plenty of limp in the soil, but yet none of the so-called limestone, every farmer must know that it vv as bettor for his land that he should buy store cattle and fatten them himself than that he should rear his own calve->, and fatten them into beef for the market. In the latter case the phosphate of the soil was carried away m tho bones of tho animals, whereas in the former the bones came from somewhoro else and ho had only to put tho beef on them. The cdves had all the bones to grow, but big lean bullocks had all then bones ready madi 1 . In fact bullocks did tho soil more gor>d than harm. When tiny went away th»y left .is much phosphato of lnne behind them as \vm there before they came. Tho deeper the roots of grass go down into the soil the more nourishment they bring up. Thistles greately improved the soil, because their long roots go down and bring up fresh food to the surfivcj. Ferns, also, while they vit*re growing, improved the soil. They were continually forming more surface soil, alworbing tho phosphate of lime, potash, wdaand magnesia, and as fern in never carried away, but generally burned on the ground it leaves on the surface everything which it took from the soil. Professor Black concluded by introducing to the audience Mr Taylor.

O.v Manures. Mr T.iylor, on coining forward, was received with applause. If they had any questions to ask him he would be voiy happy, by anxw. i ing them, to afford them all the information lie possibly could. In tlic mattci of manures it was now a settled question as to what should bo the fond of pi, nits. If they wanted to grow root crops it wjvh perfectly decided that tho mainuo should Iks phosphate of lime, but phosphate of lime in a soluble form. In the insoluble form it wan not the food of plant*. Passing on from the root crop to a wheat crop, it wan now decided that ammonia becomes necessary in addition to phosphate of lime. In England tho wheat erupts only averaged at present 27 to 30 bushels to the acre ; in Australia it was Ijsk, but in Manitoba, you would gut 40 or 50 bushels at an average, but thero the soil is extremely rich in nitrogen, ff they wanted to grow potatoes successfully, they would require to supply the plant with potash, iti addition to some phosphate of lime ; and in other soils it was necessary to have a conUUtfrable quantity of manure in the form of potanh. And so on in regard to other plants. Inferring to artificial manure*, Air Taylor said farmers could manufacture them cheaper and better themselves. By ho doing they weie sure of getting a purer and it better aiticlc. He hud been artificial manures in tho colony which weio most \ilhanously adulterated with substances which warn no eaithlygood whatever, and it was di-graceftil that faimeis should bo obliged t« pay for such stuffs. The speaker then expl uncd the general mode of procedure in the manufacture of artificial manures, giving receipts, per centagen, &c The bones were taken and reduced to a powder as fine as oatmeal. Sulphuric acid was then mixed with the ground bone, and you thus foi m a Hiilphato of lime, and the phosphate of lime becomes in thi-< way soluble. They could get as lntfh as 3V/ O fiom tho bone, it contained .">O/ to /)!%. In addition to the phoHphato of linio in the bone there was n considerable quantity of gelatin yielding 4/ of ammonia, Unfortunately there was not enough bom in the world to supply all the requirements of artificial manures. A great bulk of the phosphate of lime was im ported from various other countries. In England thero was a lot of coprnlite in which thero was a large percentage of phosphate of lime. In the case of coprolitc, however, the manure w.m not bo valuable because it did not contain ammonia. In Carolinu thero was a lot of phosphate of lime. In other countries it was found in enormous quantities. In fact there was as much in Carolina, alone, as would do England for thn next 50 years. All the phosphate manures were adapted to the growth of root crops. In the North Inland he was sorry to see they did not go in for growing root crops to any gieat extent. In the South Island according to statistics 350,000 acres ucie in loot crops, where* 1 * in the north theie wero only about 10,000 flcren. Artihei ij m inures should invariably be used in tho growth of root crops. They would find it greatly to their advantage if they got manures containing 30% of soluble lime and use it for the growth of their turaipt). The mangold won a very

gross feeder. For mangold-. ."> cwt of phosphate of lime should be mixed with '2 cwt of common salt. Mi Taylor then gave several other receipts for mainuos for wheat and other crops. Referring to tho Auckland Attilicial Manure Manufactory in connection with the froe/.ing company, Mr Taylor comphmontod Auckland mi tho excellent pioduco of the factory. All tho articles there— and he had examined them — weio abvilotely pme, ,nvl f.inncrj might have n ) dilfidencj in nsiusr them.