PREFACE SOME years ago the author was interested in the production of cyanogen compounds, but found no up-to-date work on the subject: the information with regard to these bodies in the existing chemical dictionaries was unsatisfactory and often incorrect and misleading. There were several excellent books dealing with the production and application of cyanides, but such chemistry as these books contained was mainly copied from the existing dictionaries and was characterised by the same inaccuracy and unsatisfactory nature. The chemistry of these compounds had, however, not been left unregarded, as some considerable amount of original research and information has been published in the numerous technical and scientific journals, most of which is swamped by the great tide of organic chemistry of the last quarter of a century. An attempt has been made by the author covering a number of busy years, to check the composition and properties of the cyanogen compounds, particularly the metallic salts, but although many hundreds of these compounds have been prepared and examined, the task has so far proved too great to complete, and the major portion yet remains to be accomplished. In this little book an effort has been made to rescue iii the information scattered through the scientific pressa task of no mean magnitude, as the index of many of the journals was of little if any use-to check the composition and properties of the compounds described as far as possible; and to add a small quota to our knowledge of these compounds by such reactions as were brought to light in the course of the author's work. An attempt was made to publish some of the information so obtained through the scientific societies, but it was found that the time required to comply with the petty restrictions and to conform to the stereotyped methods-usually quite irrelevant to the subjectmatter-was so great that it was much better employed in further investigation. The book has been arranged to give an outline of the compositions and properties of the various cyanogen compounds; and to describe briefly the manufacture, application and estimation of such compounds as are met with in commerce. Great care has been taken to record the various sources from which the information has been taken, and it is hoped that all such sources are duly acknowledged. |