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This eBook from the Gutenberg Project consists of approximately 102 pages of information about Scientific American Supplement, No. 415, December 15, 1883.

PLASTIC CARBON FOR BATTERIES.

Max Nitsche-Niesky recommends the following in Neueste Erfindung.:  Good coke is ground and mixed with coal-tar to a stiff dough and pressed into moulds made of iron and brass.  After drying for a few days in a closed place, it is heated in a furnace where it is protected from the direct flames and burned, feebly at first, then strongly, the fire being gradually raised to white heat which is maintained for 6 or 8 hours.  The fire is then permitted to slowly go down, and when perfectly cold the carbon is taken out of the furnace.

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RECENT STUDIES ON THE CONSTITUTION OF THE ALKALOIDS.

By SAMUEL P. SADTLER, Ph.D.

[Footnote:  Introductory lecture, Course of 1883-84, Philadelphia College of Pharmacy.]

The sciences of to-day present, as might be expected, a very different aspect from the same branches of knowledge as they appeared fifty or sixty years ago.  It is not merely that the mass of observations in most of these lines of study has enormously increased during this interval.  Were that all, the change could hardly be considered as an unmixed benefit, because of the increased difficulty of assimilation of this additional matter.  Many would be the contradictions in the observations and hopeless would be the task of bringing order out of such a chaos.  The advance in the several branches of knowledge has been largely one resulting from improved methods of study, rather than one following simply from diligence in the application of the old ways.

Let us turn to chemistry for our illustration of this.  The chemistry of the last century and the early decades of this was largely a descriptive science, such as the natural history branches, zoology, and botany are still in great part.  Reasonably exact mineral analyses were made, it is true, but the laws of chemical combination and the fundamental conceptions of atoms and molecules had not been as yet generally established.  Now, this want of comprehensive views of chemical reactions, their why and wherefore, was bad enough as it affected the study of inorganic and metallic compounds, but what must have been the conditions for studying the complex compounds of carbon, so widely spread in the vegetable and animal kingdoms.  Their number is so enormous that, in the absence of any established relationships, not much more than a mere enumeration was possible for the student of this branch of chemistry.  It is only within the last twenty years that chemists have attained to any comprehensive views at all in the domain of organic chemistry.  It has been found possible to gradually range most carbon compounds under two categories, either as marsh-gas or as benzol derivatives, as fatty compounds or as aromatic compounds.  To do this, methods of analysis very different from those used in mineral chemistry

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