Experiments upon Swedes. 15 



15. 100 seeds, sown with. 120 grs. of sulphate of ammonia and oz. of 



powdered soluble silica rock. 



16. 100 seeds with i oz. of Peruvian guano. 



17. 100 seeds without anything. 



18. 100 seeds without anything. 



The flowerpots containing these 18 experiments were regularly 

 watered every day. The soil was constantly kept in a moderately 

 moist condition, and the result observed from time to time. 



On reference to my notes, taken at the time, I find the entries 

 embodied in the following Tabular Statement. (See page 166.) 



An inspection of these Tables will show amongst other par- 

 ticulars : 



1 . That the seed employed in the experiments was of good 

 quality, 94 in one trial and 90 in a second, out of 100, having 

 germinated. 



2. That turnip-seed unprepared and merely moistened occa- 

 sionally, germinated more rapidly than the seed in all the other 

 experiments. 



3. That very dilute sulphuric acid killed the seed. 



4. That a dilute solution of sulphate of ammonia killed many 

 seeds, and retarded greatly the germination of those that sur- 

 vived. Thus two-thirds of the number of turnip-seeds were 

 killed, and only one-third germinated. It will also be seen that 

 sulphate of ammonia sown in considerable quantity with the 

 seed also killed it, whilst in more moderate doses it greatly re- 

 tarded the germination of the surviving seeds. 



5. That Peruvian guano, even in small quantities, had the 

 same effect as sulphate of ammonia : hence the danger of drilling 

 in turnip-seed or carrots with guano, even when previously 

 mixed with ashes. 



6. That superphosphate of lime, instead of hastening, rather 

 retarded the germination of turnip-seed. 



7. That superphosphate made from bones and containing 

 ammonia is more liable to injure the seed, than superphos- 

 phate made from bone-ash or mineral phosphates. Thus it 

 will be seen, that only 60 plants came up in No. 9, in which 

 bone superphosphate was used, and 80 plants in No. 10, in 

 which experiment the same quantity of bone-ash superphosphate 

 was employed. 



It follows from these experiments 



1st. That it is advisable to mix artificial manures, such as 

 guano -and superphosphate, with as large a quantity of ashes as 

 is practicable, if the manure is sown dry, and to mix the arti- 

 ficial manure with much water if the liquid manure drill is 

 used. 2ndly. That superphosphate of lime, especially when made 



from 



