1896.] Yati Bhusan Bhadurl — Hypochlorites into chlorates. 43 



2. Contrihxdions to the Theory of Warning Colours and Mimicry, 

 No. IT. Experiments %oith a Lizard (calotes versicolor). — By Frank 

 Finn, Esq., B.A., Deputy Superintendent, Indian Museum. 



3. A note on the nature of the substance formed during Indigo Fer- 

 mentation from tohich Indigo-Blue is eventtially formed and an Indigo- 

 Broion. — By Surgeon-Lieutenant-Colonel George Ranking, B.A., M.D. 



The papers will be published in the Journal, Part II. 



4. On the transformation of hypochlorites into chlorates. — By Babu 

 Tati Bhusan Bhaduei, M.A., Premcand Raycand Scholar. Communi- 

 cated by the President. 



(Abstract.) 



In the preliminary portion the various methods of estimatino- 

 chlorates and hypochlorites have been carefully examined. Direct 

 estimation of both in a mixture containing the same have been found 

 possible by distillation in moderately dilute solution with pure phos- 

 phoric acid and then the residue with fuming hydrochloric acid. Hypo- 

 chlorites can not be estimated in acid solutions (with KI and HCl) in 

 presence of chlorates. 



The action of chlorine on sodic hydrate is ascertained by passino- 

 the washed gas through a solution of the hydrate. Owing to consider- 

 able change of volume consequent on absorption, the amount of sodium 

 is determined afterwards. The total chlorine is determined by reduc- 

 tion with zinc copper couple and the hypochlorite by Penot's, or distilla- 

 tion method. From numerous experiments it is found that the amount 

 of chlorate which is formed in solution up to 7 per cent, of concentra- 

 tion and containing free alkali is insignificant. Above 10 per cent, 

 solution, however, the secondary reaction — transformation — becomes 

 more distinct and when the concentration exceeds 20 per cent., time 

 becomes an important factor. Presence of free alkali retards the 

 change. 



To study the transformation, the solution of known strength is 

 kept in stoppered bottles or sealed tubes and then exposed to rays of 

 different degrees of refrangibility or kept in absolute darkness. After 

 the required time the contents are analysed (the volume of oxygen also 

 determined). The results of the analyses prove that a solution of sodium 

 hypochlorite slowly decomposes even when kept in absolute darkness. 

 The rate of decomposition increases as the refrangibility of the rays 

 increases. Yellow rays are far more active than the red. The change 

 is one into chlorate and free oxygen. If there be little or no free 

 alkali, chlorine is simultaneously liberated. 



When the change takes place at about 100° C. strong sealed glass 



