Quarterly Abstract of European Chemistry. 181 



Art. XVIIl. — Abstracts of the Researches of European Chemists ; pre- 

 pared for this Journal by J. Lawrence Smith, M. D.* 



Guano. — From the increased importance that this manure is every 

 day acquiring, many chemists have been induced to undertake analyses 

 of the various kinds ; and as the results are of general importance, it 

 is well to give a statement of those recently made. They show a great 

 variety of composition in this substance, and the necessity that the ag- 

 riculturist is under of having its value properly estimated by a chemist 

 before purchasing, as he may give the same price for two specimens, 

 one of which may be three times as valuable as the other. 



MM. Girardin and Bidard (Ann. de Ch. et de Phys. Jan. 1844) find 

 the following ingredients in a South American variety : 



Urate of ammonia ; oxalate of ammonia ; oxalate of potash ; oxa- 

 late of lime ; phosphate of ammonia ; phosphate of potash ; phosphate 

 of lime ; phosphate of magnesia ; sulphate of potash, chloride of po- 

 tassium, and fatty matter — of the three last, very little. 



This composition is the same as that of the excrements of aquatic 

 birds and poultry. These authors are inclined to think that the guano 

 is a fossil excrement — the coprolite of some extinct race of birds. 

 Carbonate of ammonia was found in some part of the specimen exam- 

 ined, but it is not a constant ingredient, it being formed by the decom- 

 position of urate of ammonia, which takes place in a moist atmosphere. 

 The nitrogenous compounds of guano being those that fix its value, the 

 quantity present in the above mentioned specimen was estimated and 

 found to be as follows. 



Dry uric acid, . . 18-4, indicating, . . 6-13 nitrogen. 

 Ammonia, . . . 13-0, " . . 10-73 



In 100 parts of guano, 16'86 " 



This is a larger proportion of nitrogen than is commonly found ; 

 MM. Payen and Boussingault give from 5 to 14 per cent, as the result 

 of their investigations. 



E. F. Teschemacher, (Phil. Mag. May, 1844, p. 394,) in an exam- 

 ination of an African variety of guano, found 4 per cent, of humic 

 acid combined with ammonia, with scarcely a trace of uric acid. la 



* Messrs. Editors — The great interest that it affords me of ascertaining what is 

 going on from day to day in the European school of chemistry, has led me to sup- 

 pose that many of your readers might be equally interested if they had the means 

 of obtaining the information. I have therefore concluded to give quarterly notices 

 of the most interesting discoveries in chemistry, of which this is the first. 



Yours, «fcc. J. L. S. 



Charleston, Nov. 30, 1844. 



