86 Biographical Sketch of C. A. Coulomb. [August 



even the mechanical powers of different individuals depend so 

 much upon causes which are difficult to detect and impossible 

 to appreciate. In the year 1800, Coulomb published, in the 

 Memoirs of the Institute, a paper on magnetism, and likewise 

 one of his most learned essays on the cohesion of fluids. He 

 employed his torsion balance in the experimental part of the 

 inquiry -, and he was led by his experiments to form the conclu- 

 sion, ihat the resistance which fluids oppose to the slow motion 

 of their particles upon each other is represented by two terms, 

 the one proportional to the velocity of the motion, the other to 

 the square of this velocity.* 



The events of Coulomb's life are few, and not particularly 

 interesting. The French revolution deprived him of some 

 offices which he had filled under the monarchy, and probably 

 impaired his private property. At the dissolution of the 

 Academy he felt no longer any interest in the metropolis, nor 

 indeed could it be considered as a place of security for any one 

 distinguished either for talents or for acquisitions of a more inci- 

 dental kind. He retired for some time to a small estate which 

 he possessed near Blois, until the violence of the storm was 

 passed over, when he was recalled to take his place in the Insti- 

 tute, of which he continued ever after to be an active member. 

 His death took place in his 70th year, in consequence of a 

 gradual exhaustion of the nervous system, the immediate result 

 of a febrile attack, but probably originating in the decay of the 

 system incident to the decline of life. 



The moral character of Coulomb is stated by his eulogist to be 

 of a high order of excellence ; he is said not only to have 

 possessed many great virtues, but to have had few dejects 

 to counterbalance them. It is indeed admitted that he had an 

 impatience of temper, which he often found it difficult to 

 restrain ; but this seems not to have been carried to such a 

 degree as to render him unamiable, or to disqualify him for any 

 of the relations of society. The scientific reputation of Coulomb 

 has been highly estimated by those who are the best qualified to 

 judge of his merits; his mathematical learning was unquestionably 

 very profound ; and all his writings indicate a clear and correct 

 method of reasoning, united to a comprehensive view of his 



* The following are the titles of the papers published by Coulomb in the 

 Memoirs of the Institute: 



V. 2. Experiments on the Circulation of the Sap in Trees. 



V. 2. Results of Experiments to determine the Quantity of Power which 

 can be exerted by Men in their daily Labour, according to the Mode in which they 

 employ their Strength. 



V. 3. Theoretical and experimental Determination of the Forces which bring 

 different magnetic Needles to Saturation at their magnetic Meridian. 



V. 3. Experiments to determine the Cohesion of Fluids, and the Laws of their 

 Resistance in very slow Motions. 



V.4. New Method of determining the Inclination of the Magnet. 



V. 6. Results of the different Methods employed to give Plates and Bars of 

 Steel the greatest Degree of Magnetisnu 



