478 



NATURE 



[September 13, 1900 



Indeed, the only notable additions to the methods o. analysis 

 in the dry way since the time of Berzelius are the development 

 of flame reactions, which Bunsen worked out with such 

 characteristic skill and ingenuity, and the introduction of the 

 spectroscope. 



The necessity for some process other than that of analysis in 

 the dry way seems, in the first instance, to have arisen in quite 

 early times in connection with the examination of drugs, not 

 only on account of the necessity for discovering their con- 

 stituents, but also as a means of determining whether they 

 were adulterated. In such cases analysis in the dry way was 

 obviously unsuitable, and experience soon showed that the only 

 way to arrive at the desired result was to treat the substance 

 under examination with aqueous solutions of definite substances, 

 the first reagent apparently being a decoction of gallnuts, which 

 is described by Pliny as being employed in detecting adulteration 

 with green vitriol. 



The progress made in connection with wet analysis was, how- 

 ever, exceedingly slow, largely owing to the lack of reagents ; 

 but as these were gradually discovered wet analysis rapidly 

 •developed, especially in the hands of Tachenius, Scheele, Boyle, 

 Hoftman, Margraf, and Bergmann. Boyle (1626-1691) es- 

 pecially had an extensive knowledge of reagents and their 

 application; and, indeed, it was Boyle who first introduced 

 the word " analysis " for those operations by which substances 

 «nay be recognised in the presence of one another. Boyle knew 

 how to test for silver with hydrochloric acid, for calcium salts 

 with sulphuric acid, and for copper by the blue solution produced 

 by ammonia. 



Margraf (i 709-1 782) introduced prussiate of potash for the 

 •detection of iron, and Bergmann (1735-1784) not only intro- 

 duced new reagents and new methods for decomposing minerals 

 and refractory substances, such as fusion with potash, digestion 

 with nitric acid or hydrochloric acid, but he also was the first to 

 suggest the application of tests in a systematic way, and, indeed, 

 the method of analysis which he developed is on much the same 

 tines as that in use at the present day. He paid special atten- 

 tion to the qualitative analysis of minerals, and gave careful 

 instructions for the analysis of gold, platinum, silver, lead, copper, 

 zinc, and other ores. The work of Scheele (1742- 1786) had in- 

 directly a great influence on qualitative analysis, as, although 

 he did not give a general systematic method of procedure in the 

 analysis of substances of unknown composition, yet the methods 

 ■which he employed in the examination of new substances were 

 so original and exact as to remain models of how qualitative 

 .Analysis should be conducted. 



Great strides in analytical chemistry in the wet way were made 

 •through the work of Berzelius, who, by the discovery of new 

 aiiethods, such as the decomposition of silicates by hydrofluoric 

 acid and the introduction of new tests, greatly advanced the art. 

 He paid special attention to perfecting the methods of analysis 

 ■of mineral waters, and these researches, as well as his work on 

 ores, and particularly his investigation of platinum ores, stamp 

 Berzelius as one of the great pioneers in qualitative and quanti- 

 tative analytical chemistry. 



By the labours of the great experimenters whom I have 

 mentioned qualitative analysis gradually acquired the familiar 

 appearance of to-day, and many books were written with the 

 object of arranging the mass of information which had accumu- 

 lated, and of thus rendering it available for the student in his 

 efforts to investigate the composition of new minerals and other 

 substances. Among these books maybe mentioned the " Hand- 

 buch der analytischen Chemie," by H. Rose, and especially 

 the well-known analytical text-books of Fresenius, which have 

 had an extraordinarily wide circulation and passed through many 

 editions. 



The work of the great pioneers in analytical chemistry was 

 work done often under circumstances of great difficulty, as before 

 the end of the seventeenth century there were no public insti- 

 tutions of any sort in which a practical knowledge of chemistry 

 could be acquired. Lectures were, of course, given from very 

 «arly times, but it was not until the time of Guillaume Fran9ois 

 Rouelle (i 703-1 770), at the beginning of the eighteenth century, 

 that lectures began to be illustrated by experiments. Rouelle, 

 •who was very active as a teacher, numbered among his pupils 

 •many men of eminence, such as Lavoisier and Proust, and it was 

 largely owing to his influence that France took such a lead in 

 practical teaching. In Germany progress was much slower, 

 and in our country the introduction of lectures illustrated by 

 ■experiments seems to have been mainly due to Davy. 



When it is considered how slowly experimental work came to 

 be recognised as a means of illustration and education, even in 

 connection with lectures, it is not surprising that in early times 

 practical teaching in laboratories should have been thought quite 

 unnecessary. 



The few laboratories which existed in the sixteenth century 

 were built mainly for the practice of alchemy by the reigning 

 princes of the time, and, indeed, up to the beginning of the nine- 

 teenth entury, the private laboratories of the great masters were 

 the only schools in which a favoured few might study, but which 

 were not open to the public. Thus we find that Berzelius re- 

 ceived in his laboratory a limited number of students who worked 

 mostly at research ; these were not usually young men, and his 

 school cannot thus be considered as a teaching institution in the 

 ordinary sense of the word. 



The earliest laboratory open for general instruction in Great 

 Britain was that of Thomas Thomson, who, after graduating in 

 Edinburgh in 1799, began lecturing in that city in 1800, and 

 opened a laboratory for the practical instruction of his pupils. 

 Thomson was appointed lecturer in Chemistry in Glasgow 

 University in 1807, and Regius Professor in 1818, and in Glasgow 

 he also opened a general laboratory. 



The first really great advance in laboratory teaching is due 

 to Liebig, who, after working for some years in Paris under 

 Gay-Lussac, was appointed in 1824 to be Professor of Chemistry 

 in Giessen. Liebig was strongly impressed with the necessity 

 for public institutions where any student could study chemistry, 

 and to him fell the honour of founding the world-famed Giessen 

 Laboratory, the first public institution in Germany which 

 brought practical chemistry within the reach of all students. 



Giessen rapidly became the centre of chemical interest in 

 Germany, and students flocked to the laboratory in such numbers 

 as to necessitate the development of a systematic course of 

 practical chemistry, and in this way a scheme of teaching was 

 devised which, as we shall see later, has served as the founda- 

 tion for the system of practical chemistry in use at the present 

 day. 



When the success of this laboratory had been clearly estab- 

 lished, many other towns discovered the necessity for similar 

 institutions, and in a comparatively short time every university 

 in Germany possessed a chemical laboratory. The teaching of 

 practical chemistry in other countries was, however, of very 

 slow growth ; in France, for example, Wurtz in 1869 drew 

 attention to the fact that there was at that time only one labora- 

 tory which could compare with the German laboratories, namely, 

 that of the Ecole normale superieure. 



In this country the provision of suitable laboratories for the 

 study of chemistry seems to date from the year 1845, when the 

 College of Chemistry was founded in London, an institution 

 which under A. W. Hofmann's guidance rapidly rose to such a 

 prominent position. 



In 1851 Frankland was appointed to the chair of chemistry in 

 the new college founded in Manchester by the trustees of John 

 Owens, and here he equipped a laboratory for the teaching of 

 practical chemistry. Under Sir Henry Roscoe this laboratory 

 soon became too small for the growing number of chemical 

 students, a defect which was removed when the new buildings of 

 the college were opened in 1873. In 1849 Alexander Williamson 

 was appointed Professor of Practical Chemistry at University 

 College, London, where he introduced the practical methods of 

 Liebig. 



Following these examples, the older universities gradually 

 came to see the necessity for providing accommodation for the 

 practical teaching of chemistry, with the result that well- 

 equipped laboratories have been erected in all the centres of 

 learning in this country. 



Since Liebig, by the establishment of the Giessen Laboratory, 

 must be looked upon as the pioneer in the development of prac- 

 tical laboratory teaching, it will be interesting to endeavour to 

 obtain some idea of the methods which he used in the training of 

 the students who attended his laboratory in Giessen. From 

 small beginnings he gradually introduced a systematic course of 

 practical chemistry, and a careful comparison shows that this 

 was similar in many ways to that in use at the present day. 

 The student at Giessen, after preparing the more important 

 gases, was carefully trained in qualitative and quantitative 

 analysis ; he was then required to make a large number of 

 preparations, after which he engaged in original research. 



Although there is, as far as I have been able to ascertain, no 

 printed record of the nature of the quantitative work and the 



NO. 161 I, VOL. 62] 



