376 



SCIENCE 



[N. S. Vol. LII. No. 1347 



But it seems to me tliat the difficulties of our 

 time plead loudly for a broadening of the pur- 

 pose and a shapening of the "weapons of anthro- 

 pology. If we elect to stand where we have 

 done a new science will respond to the needs 

 of state and society ; it will spring from medi- 

 cine and psychology, it will be the poorer in 

 that it knows little of man's development, little 

 of his history or pre-history. But it will de- 

 vote itself to the urgent problems of the day. 

 The future lies with the nation that most 

 truly plans for the future, that studies most 

 accurately the factors which will improve the 

 racial qualities of future generations either 

 physically or mentally. Is anthropology to lie 

 outside this essential function of the science of 

 man ? If I understand the recent manifesto of 

 the German anthropologists, they are deter- 

 mined it shall not be so. The war is at an end, 

 but the critical time will be with us again, I 

 sadly fear, in twenty to thirty years. How 

 will the states of Europe stand then? It de- 

 pends to no little extent on how each of them 

 may have cultivated the science of man and 

 applied its teaching to the improvement of 

 national physique and mentality. Let us take 

 care that our nation is not the last in this 

 legitimate rivalry. The organization of exist- 

 ing human society with a view to its future 

 welfare is the crowning task of the science of 

 man; it needs the keenest -minded investiga- 

 tors, the most stringent technique, and the ut- 

 most sympathy from all classes of society itseK. 

 Have we, as anthropologists, the courage to 

 face this greatest of all tasks in the light of 

 our knowledge of the past and with our 

 understanding of the folk of to-day? Or shall 

 we assert that anthropology is after all only a 

 small part of the science of man, and retreat 

 to our study of bones and jxatsherds on the 

 ground that science is to be studied for its own 

 sake and not for the sake of mankind? I do 

 not know what answer you will give to that 

 question, yet I am convinced what the judg- 

 ment of the future on your answer is certain 

 to be. 



Karl Peak son 



SULPHUR AS A FERTILIZER 



Information concerning the relation of sul- 

 phur to plant nutrition and growth has been 

 accumulating during the last decade, and the 

 mass of data has now become so important that 

 it demands recognition of all investigators of 

 nutritional problems. Indeed, it seems to me 

 tliat much of our past experimental field work 

 dealing with the influence of fertilizer ele- 

 ments upon plants has been so loosely done that 

 we are under the necessity of reexamining the 

 whole matter. 



Although the value of sulphur, particularly 

 in the form of gypsum, was recognized at an 

 early period in our national history, the lack 

 of uniform success with it soon led to its neg- 

 lect as an important fertilizer. And after the 

 invention of acid phosphate about the middle 

 of the last century, the development was al- 

 most wholly toward soluble fertilizers contain- 

 ing nitrogen, phosphorus, and potassium. Sul- 

 phur was not included as a part of a complete 

 fertilizer, although it was recognized as neces- 

 sary to plant growth. The soil was thought 

 to contain enough sulphur, and plants to need 

 so little of it, that it was added to the soil only 

 incidentally, as in acid phosphate, potassium 

 sulphate, or ammonium sulphate, along with 

 the three elements forming the so-called 

 " complete " fertilizer. 



Experiment station workers and other stu- 

 dents of mineral nutrition of plants fell into 

 loose ways of working with fertilizer salts. 

 They have not hesitated to use sulphur-con- 

 taining nitrogenous compounds when testing 

 the influence of increased nitrogen on plant 

 growth. Similarly the acid phosphate has 

 been used in testing the effects of phosphorus; 

 and potassium sulphate has been used when 

 potassium was under observation. In compar- 

 ing various forms of fertilizer elements we 

 find the superphosphate for instance pitted 

 against bone meal; or potassium sulphate 

 against potassium chloride; or ammonium sul- 

 phate against sodium nitrate as a source of 

 nitrogen. It is evident that such tests as these 

 are all invalid if sulphur itself is shown to be 

 an important fertilizer element. For the ex- 



