while, if the same soils are inoculated with cultures . of these bacteria, tubercles are formed abundantly ' and a large assimilation of nitrogen takes place. It will be remembered that in Dr. Pugh's 'experi ments the soils were ignited and washed to remove nitrogen compounds ; in other words, be worked with sterilized soils, and, of course, obtained no as similation of nitrogen. At ,that time the devel opments of modern bacteriology were undreamed of and the experimenters had no suspicion that by thus treating the soil they were radically altering the conditions of the experiment. It is still true that under the conditions of their experiments, plants do not utilize free nitrogen. What recent ex periments have shown is that the conditions of their experiments were not those which prevail in nature. Another thing which is strikingly brought out by these more recent results is the fact that any belief regarding natural phenomena, which is wide ly prevalent among intelligent tillers of the soil is extremely likely to have some basis in fact, and that it is not safe to ignore the minute, if not al ways accurate, observations of the agriculturist. His belief may nit be true in the form in which he holds it, but it is altogether likely that it con tains at least the germ of a truth. A paper by Nobbe and others, recently publish ed, gives some additional points of interest regard ing this most important agricultural process. For example, the methods of obtaining pure cultures of bacteria which are in use by the bacteriologist were successfully applied to these organisms, and plants grown in sterilized soils inoculated from these pure cultures developed tubercles and assim ilated free nitrogen. Perhaps the most interesting result however, was that the tubercles of leguminous plants are in all probability produced either by different species of bacteria or by different modifications of the same species, and that, for example, the bacteria of the pea failed to produce tubercles upon the lupine and vice versa. In conclusion, a word may not be out of place as to the agricultural importance of the activity of THE FREE LANCE. these minute organisms. Nitrogen is not only in dispensable to the formation of all organized tis sue, but, agriculturally speaking, is the most cost ly and the most elusive element of plant food with , which the farmer has to deal. Like the poet's gold it is "Heavy to get and light to hold." By leaching and drainage on the one hand it escapes into the rivers and the sea, and by fermentation and volatilization on the other hand it finds its way into the air, while its replacement in the form of fertilizers makes large demands on the. fax pocket-book. Indeed, from the standpoint of fif teen years ago, it seemed that the destructive forces had the upper hand, and that the stock of combin ed nitrogen in the world was steadily diminishing. With our present knowledge the case is revers ed. The world's supply of available nitrogen, in stead of being a limited and perhaps diminishing quantity, is practically illimitable. In this, as in other cases, we are coming to recognize in these invisible organisms not only the deadly foes which give rise to consumption, cholera, yelow fever and other infectious and contagious diseases but, as well, the friends to whose activity we are indebted. for many of the luxuries and even necessaries of life. THE COLLEGE STUDENT AND READING. In the newer college courses where a large part of the students time is absorbed with mathemati cal studies, and their application in laboratory' work, reading is likely to be neglected. I do not mean noltal reading or even newspaper or magazine reading, but the loftier expression on the profound questions of life, that are found in only a few books, comparatively. While I do not think of suggesting a long list of books which a young man would be expected to wade through, as a duty, yet there are some authors whom he should read for the inspiration and the new awak ening of the imagination which they give. Per haps few authors are more provocative of thought
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