1} E K 



322 



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erth. according to M. Berthollet's iilcai, eught to fall d > n 

 in combination with a portion of acid. Hi .' 

 potass* be poured into a itulphiiric solution of magnesia, the 

 produit-d. alter Wing well wash*!, affords no 

 ..f the presence of aeld"j and M. Pfaff has shown, 

 by some very decisive experiment!*, that i has no 



action upon neutral combinations of thu alkalies and sul- 

 phuric acid ; and likewise that the tartareous arid is 

 entirely separated from lime, and the oxalic acid from 

 oxide of lead by quantities of sulphuric nci<l merely suffi- 

 cient to saturate the two bases: and these are distinct and 

 simple instances of elective attraction. Again, when one 

 mot.il precipitates another from an acid solution, the body 

 that falls down is usually free both from acid and oxygen ; 

 thus zinc precipitates lead and tin, and iron, copper : and 

 the whole of the oxygen and the acid is transferred from 

 one metal to the other. 



' M. Berthollet, in crystallizing sulphate of potassa from 

 acid solutions, states that he obtained salt*, of which the 

 first portion contained 55'83 of acid in 100 parts, and another 

 portion only 49-5 ; but it is far from improbable that these 

 salts were both mixtures of the acidulous sulphate and the 

 neutral sulphate of potash ; and the idea is strengthened 

 by the circumstance that ho obtained neutral sulphat 

 the same solution, towards the end of the pnK-ess : but 

 even allowing the substances to have been principally 

 simple binary combinations, and not mixtures, still the 

 potassa and the acid may be regarded in them as inde- 

 finite proportions. The number representing potassa being 

 considered as 90, and that representing sulphuric acid 

 as 15, the first may be conceived to contain four of alkali 

 and seven of acid, and the second, three of alkali and four 

 of acid. 



' In cases in which solutions of salts are formed in acid or 

 alkaline menstrua, which are supposed incapable of decom- 

 posing them, the results must be considered as depending 

 upon a new combination ; and in the evaporation of the 

 water or of the menstruum, and the crystallization of the 

 remaining constituents, the proportions that have acted 

 will determine the nature of the solids which are formed. 

 There appears no difficulty in reconciling the doctrine of 

 definite proportions with the influence of quantity ; none of 

 the experiments of M. Berthollet can be considered as 

 strictly contradictory to the doctrine, and some of the most 

 important results of this sagacious chemist afford it con- 

 firmation. 



' M. Kerthollec supposes that the attraction of tiodies for 

 each other are inversely as the quantities that saturate. 

 Thus, magnesia and ammonia take up more sulphuric acid 

 than equal quantities of potassa, and therefore he concludes 

 that magnesia and ammonia have a stronger attraction for 

 acids than potassa ; yet potassa instantly separates magnesia 

 and ammonia from acids, and though the facility with 

 which ammonia is expelled from a compound may be hypo- 

 thetically accounted for, by assuming that the ease with 

 which it takes the gaseous state assists its escape ; yet 

 magnesia is in an opposite case, and to account for oh 

 changes by supposing the effects of forms of matter which 

 are about to appear, or powers not in actual existence, such 

 as elasticity or cohesion, is merely the solution of one diffi- 

 culty by the creation of another, and ammonia when solid 

 or fluid should require a new force to render it elastic ; and 

 the cohesion in a compound can only be regarded as the 

 exertion of the chemical attractions of its elements. Tho 

 action betwen the constituents of a compound must he 

 mutual; sulphuric acid, there is every reason to ! 

 has as much attraction for baryta as baryta for sulphuric. 

 acid; and baryta is the alkaline substance of which the, 

 largest quantity is required to saturate sulphuric, acid ; 

 then-fore, on M. Bcrtholiet's view.it has the weakest affinity 

 for that acid ; but less sulphuric acid saturates this sub- 

 stance than any other earthy or alkaline body ; therefore, 

 according to M. Bert1ollet, sulphuric acid has a stronger 

 affinity for baryta than for any other substance, which is 

 contradictory.' 



In a controversy which Berthollet had with Proust, ho 



maintained an opinion which now seems too extraordinary 



ever to have been broached, that bodies are capable of 



iiiing in all proportions. The discussion was carried 



on HI ut equal courtesy on both side-, and 



v with which Berthollet sustained bis 



in Illo-l IMT-OIIS could have brought to 



their support, it U now universally admitted that his 



' were totally inaccurate, while those of Proust have acquired 

 fresh proof from the din-trine of definite proportions. 



Several . iin-h pro\c the moral and personal 



courage of Berthollet, are 01. :, we shall 



one only. During the Reign of Terror, u short nine ': 

 the 9th Thermidor, when it was tin- -\-t.-m to rai-e up pre- 

 tended plots to give pretexts for putting to death tho-e who 



obnoxious to Robespierre and ' 

 notice was given, at u sitting of the ( of 1'nhli'c 



. that B coii-piran, had just beei, 

 the soldiers, by p hi brandy which was 



. out to them previous toun -, said 



that the siek in the hospitals who bad la-ted this brandy 

 all perished in consequence of it. Immc<: 

 issued to arre-t tho-o prevjouMv marked I n, A 



quantity of the brand) was >ent to BI-II 

 He was informed, ut the same time, that Hobespi. 

 a conspiracy to be established, and all knew thai 

 to liis will' was certain destruction. Having finished his 

 analysis, Berthollet drew up his results in a report, which 

 he accompanied with n written explanation of his 

 and he there stated, in the plainest language, that nothing 

 ous was mixed with the brandy, but that it had been 

 diluted with water holding small particles of slate in sus- 

 pension, an ingredient which filtration would remove. This 

 report deranged the plans of the Committee of Public Safety. 

 They sent fir the author t him of the 



of his analysis, and to persuade him to alter its r. 

 Finding that he remained unshaken in his opinion. K 

 pierre exclnimed, ' What, Sir! darest thou allirm that thu 

 muddy brandy is free from poison ?' Berlbollet immediately 

 filtered a gl.iss of it in l.is presi nee. and drank it oft. 'Thou 

 art daring, Sir, to drink that liquor,' exclaimed the ferocious 

 president of the committee. ' I dared much more,' replied 

 Berthollet, 'when I signed my name to that Report.' 1 

 can be no doubt that he would have paid the penalty of this 

 undaunted honesty with his life, but that fortunately the 

 Committee of Public Safety could not at that time dispense 

 with his services. 



Upon his return from Egypt, Berthollet was nominated a 

 senator by the first consul ; and afterwards received the dis 

 Unction of grand officer of the Legion of Honour, grand 

 cross of the order of Re-union, und, under the emperor he 

 was created Count, after the restoration of the Bourbon he 

 was created a peer of France. The advancement to these 

 offices produced no change in the manners of Berthollet. 

 Of this he gave a striking proof, by adopting, as his armo- 

 rial bearing (at the time that others eagerly blazoned some 

 exploit), the plain unadorned figure of his faithful and 

 affectionate dog. He was no courtier before he received 

 these honours, and he remained equally simple and un- 

 assuming, and not less devoted to science, after they were 

 conferred. 



The latter years of his life were embittered by the mis- 

 conduct and suicide of his son, M. Amod< e Berthollet, who 

 had distinguished himself by his chemical researches. In 

 be was attacked by a slight fever, which left behind it 

 a number of boils: these were soon followed by a gangre- 

 nous ulcor of uncommon size. Under this he suffered for 

 several months with surprising fortitude. Ho himself, as 

 a physician, knew the extent of his danger, felt the im-\i- 

 table progress of the malady, and calmly regarded the slow- 

 approach of death. At length, after a tedious period of 

 suffering, in which his equanimity had never once been 

 shaken, he died on the 6th of November, when he had 

 nearly completed the 74th year of his age. 



BERTHOLLE'TIA, a remarkable plant belonging to 

 the natural order Lecythideef. It is of large diuien- 

 and forms vast forests on the banks of the Oronoko. Its 

 stem averages a hundred feet in height, and I wo feet in 

 diameter, not branching till neartlie top, whence its houghs 

 hang down in a graceful manner. Its leaves are undivided, 

 arranged alternately upon the branches, about two feet 

 long, ami live or six inches wide, of a brilliant green. Its 

 HIM ITS are vellowish white, with a calyx having a decidu- 

 ous border, divided into two pieces, a corolla of six unequal 

 petals joined together at the base, and a very great number 

 of white stamen- joined into a thick fleshy ring. The fruit 

 is figured and dcscril>ed In Hmiiboldl as a spherical ra-o, 

 as bii: :i a man's head, with four cells, in each of which are 

 six or eiuhl nuts ; it- shell is rugced and furrowed, and 

 covered with a rind of a green colour. The nuts are irre- 

 gularly triangular bodies, having a hard shell, which u 



