366 



RO BI SON. 



Hobison, Upon the death of Dr. Russell in 1773, Principal 

 John> Robertson, though not personally acquainted with our 

 '""Y"*' author, recommended him to the vacant chair of natu- 

 ral philosophy in the University. The patrons of the 

 University readily yielded to this recommendation, 

 and as the Russian government offered to increase the 

 salary and appointments of Mr. Robison, it was with 

 some difficulty that he came to the resolution of settling 

 in his native country, and of sitting in the next chair 

 to Dr. Black. Finding it in vain to offer any farther 

 inducement to detain him in Russia, the Empress gave 

 him a pension of 80 per annum, accompanied with a 

 request that he would take under his care two or three 

 of the young cadets, who were to be selected in suc- 

 cession. Mr. Robison left Cronstadt in June 177*. 

 He was admitted into the College on the 16th Septem- 

 ber 1774, and delivered his first course of lectures 

 in the following winter. The system of mechani- 

 cal philosophy which he taught, embraced dynamics, 

 astronomy, mechanics, hydrodynamics, optics, elec- 

 tricity, and magnetism ; but he generally enlarged so 

 much upon the early subjects of his lectures, that 

 some of the last of these series were every year omit- 

 ted entirely in the course. When we consider that a 

 great proportion of the students of this class are stu- 

 dents of divinity, from 15 to 17 years of age, who re- 

 quire a general knowledge of natural philosophy, it is 

 not difficult to point out the nature of the course which 

 should be pursued. Mr. Robison always supposed a 

 degree of mathematical knowledge among his students 

 which they never possessed, and even if they had gone 

 through the requisite course, either at the University 

 or with private masters, it by no means followed that 

 -they were able to bring this knowledge to bear in fol- 

 lowing a train of oral reasoning. In consequence of 

 this, and of the small number of experiments which he 

 introduced, and which he held as very subordinate 

 parts of his lecture, his students, with the exception of 

 a few, made very little progress in the physical 

 sciences. 



Although Mr. Robison's lectures had thus an unpo- 

 pular aspect, yet they were listened to with delight by 

 those who had devoted their minds to the subject ; and 

 who now consider themselves fortunate in having at- 

 tended the University, when he had health enough to 

 go through the labours of the course. Dr. Robison 

 never condescended to become a dealer in scientific 

 shows, to amuse his students with the exhibition of 

 trifling instruments and experiments, fit only for the 

 nursery, to occupy their time with conceits and extra- 

 vagancies of his own; to falsify the history of science 

 for the purpose of elevating himself, or to sneer at 

 those venerable men whose names have been consecra- 

 ted by time, and those revered opinions which have 

 commanded the assent of the wisest as well as the 

 best ages of the world. Like his eminent successor in 

 the chair, Professor Playfair, his great object was to 

 instruct his students in the sciences, to give just and 

 candid estimates of the labours of others, and to impress 

 upon the minds of the young those great lessons of 

 humility and piety, which the study of the material 

 world is so well calculated to teach. 



Soon after his return from Russia, Mr. Robison be- 

 came a member of the Philosophical Society, which 

 had existed since 1739- When it was incorporated 

 with the Royal Society, which was established in 1781, 

 Mr. Robison was appointed general secretary, and con- 

 tinued to discharge the duties of that office till the state 

 of his health compelled him to resign. 



It is a-curious circumstance, that. Professor Robison 

 never appeared as an author, till the year 1786, when, 

 in the 47th year of his age, he published in the Trans- 

 actions of the Royal Society of Edinburgh, A determina- 

 tion of the orbit and the mntion <J (he Georgium Sidus, 

 dirtcth/from observation. The elements tu'the orbit of 

 this planet, though deduced from observations marls 

 with an instrument fixed from a window, do not differ 

 widely from those which have more recently been 

 obtained from more numerous observations, and by 

 means of better instruments. 



The second, and the only other paper which Profes- 

 sor Robi on communicated to the Royal Society of 

 Edinburgh, was read on the 7th April, 1788, and is 

 entitled, On the Motion of Lighl, as affected by Re- 

 fracting and Reflecting Substances, ivluch are also in 

 mo'ion, and relates principally to the correction of 

 some errors of Boscovich respecting the effects of a te- 

 lescope, the tube of which is filled with water instead 

 of air, upon the aberration of light. The celebrated 

 Italian philosopher had rashly announced that if a wa- 

 ter telescope were directed to a terrestrial object pro- 

 perly situated, it will deviate from that object by a 

 certain determinate quantity every day ; but Professor 

 Robison has shown that this result is not deducible 

 from Boscovich's own principles. 



This paper was drawn up when Mr. Robison was in 

 very bad health ; and for the purpose, as he remarks, 

 " of ascertaining his claims to any thing which may 

 be valuable in his speculations." He hid been attack - 

 . ed. in December 1785, with a severe disorder, which 

 baffled all the skill of his medical friends, and which, 

 though it did not materially injure his general health, 

 continued to afflict him during the rest of his life. 



Notwithstanding this indisposition, he engaged, 

 about the year 1793, to contribute various scientific ar- 

 ticles to the edition of the Encyclopedia Britannica, 

 which was then publishing. This work never had been 

 under the charge of any literary or scientific man, till it 

 came under the management of Dr. Gleig; and therefore 

 the aid of such an editor and of such a contributor as Dr. 

 Robison, formed an era in its history. Dr. Robison revis- 

 ed and enlarged the article Optics, which was followed 

 by the article Philosophy, which he wrote jointly with 

 Dr. Gleig. His own articles are, Physics, Pneumatics, 

 Precession, Projectiles, Pumps, Resistance, Rivers, Roof, 

 Ropemaking, Rotation, Seaman skip, Signal, Sound, Spe~ 

 cijic Gravity, Statics, Steam, Steam- Engine, Steelyard, 

 Strength of' Materials, Telescope, Tide, Trumpet, Varia- 

 tion, and Waterworks. In a bound copy of Mr. Robi- 

 son's articles, labelled with his own hand, and now be- 

 fore us, we find the articles Perspective, Plough, and 

 Russia, which it is probable he also wrote. 



A Supplement to the third edition of the Encyclopedia 

 Britannica was published some time afterwards by dif- 

 ferent proprietors, and to this work Mr. Robison con- 

 tributed the following articles : Arch, Astronomy, Bos- 

 covich's Theory, Carpentry, Centre, Dynamics, .Electri- 

 city, Impulsion, Involution, Machinery, .Magnetism, 

 Mechanics, Percussion, Piano-Forte, Position, Tempera- 

 ment, Thunder, Trumpet, Tschirnhaus, and Watch-work. 

 11 To those who may examine," says Dr. Brewster, 

 in his preface to Dr. Robison's System of Mechanical 

 Philosophy, < these dissertations with a critical eye, ii 

 may be necessary to state, that they were composed un- 

 der the influence of that painful disease, with which hi 

 was afflicted for a long period of years. The knowledg< 

 of mechanical philosophy which they everywhere dis 

 play, possesses the rare quality of being at once practi*- 



