IRISH GARDENING 



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dried by sun and wind they assume the well- 

 known form of g-uano, which was the first 

 artificial fertilizer or "bag- manure " to be used 

 in this country. Guano contains a considerable 

 quantity of phosphates, a small amount of 

 potash and nitrogen in smaller or greater 

 quantity according to the amount of rainfall 

 to which the deposits have been exposed. 



The bulk of vegetation is designed to aid in 

 nutrition and growth of animal bodies. When 

 the latter decay or are consumed by other 

 animals, the hard, bony skeleton usually re- 

 mains behind, obviously consisting of materials 

 which have been removed from the soil. That 

 they can be ill-spared there is shown by the 

 healthy veg-etation which springs up when the 

 bones are broken and scattered over its surface. 

 Their value is due to the large amount of 

 phosphates which they contain, these phos- 

 phates being present in a form that only very 

 slowly dissolves in the soil, even when the 

 bones are finely crushed and applied as bone 

 meal or bone flour. In order to make the 

 phosphates of more immediate use to vegeta- 

 tion, bones are often dissolved by vitriol, which 

 changes the phosphates into a condition that is 

 easily dissolved by the water in the soil, and 

 thus enables the crop to make use of them 

 at once. Bone superphosphate or dissolved 

 bones is the name given to the manure pro- 

 duced in this way. It is a very valuable 

 manure, as it contains, in addition to the phos- 

 phates mentioned, a small amount of nitrogen. 

 It is at once apparent that the supply of bones 

 for the production of this manure must neces- 

 sarily be limited, while there has been an 

 increasing demand for this class of fertilizer, 

 as cultivators of the soil realised the benefits to 

 be derived from its use. To keep pace with 

 this increasing demand, the manure manufac- 

 turer was forced to look elsewhere for the 

 means of producing phosphatic manures ; this he 

 found in deposits of phosphatic minerals which 

 were discovered in various parts of the world — 

 in England, where the small deposits were soon 

 exhausted ; France, Belgium, Spain, Algeria, 

 United States and Canada ; the present day 

 supplies being mainly obtained from the last- 

 named countries. The phosphates are present 

 in these rocks in an insoluble form, and must 

 be changed before being of any value to plants. 

 The necessary change is brought about by 

 g'rinding the rock and dissolving it in strong 

 sulphuric acid ; the resulting product is the 

 well-known, and now widely used, superphos- 

 phate of lime, or mineral superphosphate. The 

 remains ot fish, teeth, bones, &c., are often found 

 embedded in these rocks, indicating that they had 

 an animal origin It seems probable that they 

 were deposited on submarine banks which had 

 been frequented by fish for long periods, and that 



the accumulated skeletons were covered with 

 sand and mud, and finally consolidated into rock. 

 Varying amounts of phosphates are found in 

 many ores of iron, and if allowed to remain the 

 quality of the manufactured iron would be 

 seriously injured. Lime possesses the power 

 of attaching itself to those phosphates, and ad- 

 vantage is taken of this to remove them. Iron 

 ore, coal and limestone are placed in the iron 

 furnace together, and the great heat required 

 to melt the iron causes the phosphates and lime 

 to unite in the form of a slag, which is then re- 

 moved from the furnace. This slag hardens 

 into rock-like lumps on cooling, and when these 

 lumps are crushed into an extremely fine 

 powder the product is sold as " phosphate 

 powder," or as it is now more generally known, 

 " basic slag." Besides phosphate of lime, this 

 manure also contains a certain amount of 

 ordinary lime which, no doubt, adds considerably 

 to the usefulness of the manure in many cases. 



[To be continucd.\ 

 5^* ^^ ^^ 



Zonal Pelargoniums as Window Plants. 



I DO not know of any window plant which gives 

 better returns i'or the small amount of labour needed 

 to bringf it to perfection than the Zonal Pelargonium. 

 When well grown those plants will continue to develop 

 an abundance of bloom almost the whole season through. 

 Cuttings, if inserted this month in sandy soil, will be well 

 rooted by the end of August. In potting use a compost 

 of three parts fibrous soil, one part leaf-mould, with 

 enough sand to keep the whole porous. Plenty of drain- 

 age should be afforded by means of crocks, with moss or 

 half-decayed leaves over these, so as to allow the escape 

 of superfluous water. Careful watering is, perhaps, the 

 most important factor in their management, and in many 

 cases there is a tendency to overdo it — very often from 

 a too eager desire for their welfare. The only general 

 rules that can be followed are — In winter keep the plants 

 rather dry ; in spring increase the quantity as they grow 

 and as the sun's power increases, keeping them in a 

 medium state of moisture ; in summer apply water daily, 

 and in autumn apply less as the days shorten. A little 

 observation when the plants are growing will soon give 

 the proper clue with regard to watering. In order to 

 promote a bushy growth and an increased production of 

 flowers it is essential to stop the growth of the leading 

 shoots ; this stopping, which is identical with pinching, 

 should be done when root-action is active ; the shoots 

 pinched will then push growths from dormant eyes lower 

 down. These in due time, if afforded plenty of air and 

 light, will give a good display of bloom, and repay the 

 cultivator for the little attention given to them during 

 the growing season. James Grknnan. 



Salvia. — There is quite a host of salvias (among others 

 being the common sage), some of which are hardy, and 

 others require a greenhouse. These last include some 

 very showy flowers that are at their best in autumn, and 

 afford a pleasing variety to the chrysanthemums which 

 are so conspicuous at that season. They are Salvia 

 bethelli, pink ; 5. boliviana, scarlet ; 5. pitcheri, blue ; S. 

 rutans, red ; .S'. splendens, scarlet. All are easily raised 

 from cuttings of ripened shoots in spring, and potted on, 

 much as one would the fuchsia. Of late years the salvias 

 have been little grown, but it is difficult to understand 

 why flowers so brilliant in every way during the winter 

 months are not more considered. Gko. Fraser. 



