( 4.s:} ) 



lil IIkii.s'I'KINs " I liiii<ll>iicli", li(»\\('\ er, llicsc coiiiimiiiimI^ ure (IcmtÜkmI 

 as (loiililc ('oihixmiikIs of salts dl' siil|tli(iii('arlH»\ vlic acid willi iiciilral 

 siilpiiiiric ('stcfs. 



V\)\- a loiiii' time, li(»\\ ('\('i\ I lia\(> fell serious ohjcclioiis to this 

 llicoi-v. 1 had already repeale(l tlie experiiiieiits with sid|ili(Miacelic 

 arid and iiielasid|»h(il)eMz,(>ic acid l»iit did not olilaiii pure c(Mii|>(iiiiids. 

 I was also mihiiccessl'id in atteniptiiiL»' a synthesis Ity means of the 

 salts of snl|>honcarl)()\ylic acids and dimelhyl- and diaethylsnlphate. 

 The pheiKuneiia observed dnriiiL»' this research induced me to i-e(|nost 

 Dr. Attk.m.v to try to obtain coniponnds of the same empii-ical 

 com|»osilion in a diirerent manner, namely by briiiüinu' touether 

 in niolecnlar proportions the barinm salts of the acid esters of mela- 

 sidphoben/oic acid with the barinm salts of the alkylsulphuric acids. 

 if in litis proportion they yield a compound this oiii>hl then to lia\e 

 the same empirical com|>ositioii as the last named compound. 



Dr. Attk.ma how obsei-\ed that on e\apoi'atin,u- a solution coiitaininti,' 

 in molecidai' |U'0|»orlions the barium salt of the ethyl ester of meta- 

 snlph(tben/oic acid and bai'inm ethylsidphalo. tho uroaier poi'tion of 

 the ethylbarium ^alt of inetasulphoben/.oic acid was deposited lii'sl 

 in Ixwutifid crystals: aftei' this ;i double compound (»f the two bai'inm 

 sails nia<le its apjtearance in the form of lai'.H'e rosetles of tender 

 iieodle-shaped crystals w hilsi from the motherlicpior barium elli\ 1- 

 snlphale was obtained, if an excess of barium etliy Isiilphale is taken 

 for instance, 5 ü'rams of the same to I u'raiii of the salt of barium 

 ester the double c(miponnd separates imiiKMliately and frcuii the 

 molherli(pior barium ethylsulphate is obtained. The doiible coiiipoiiud 

 cannot be recrystallised from water: its a(pieoiis solution presents 

 ihe same phenomena as one c(uilaiiiiii,u' in moleciilai' proportion 

 the \\\() salts: on e\ a|)oratioii, \\\o salt of bai'inm ester crystallises 

 lirsl, IIkmi the doiTole c<nnpon]id and liiially the barium ethylsulphate. 

 As the double compound cauiiol be recrystallised from alcohol it 

 was freed from motlierli(pioi' by striuin' pressure and analysed. Tli<' 

 results of the analyses of three diU'ereiit preparations were coiicor<laiit 

 and agreed with die formula : 



lia 1 ((', 11. SO,)., lla 1 (I II, O. 





Dr. AttI'.mv has afterwards repealed Sri:\(;r,i/s ineth(Hl of preparing' 

 the compounds, but here he als(» obtained first the elli\ I barium salt 

 of melasLilphobeiizoic acid and afterwards, allhongh letis readily, 



