160 A. Pedler — Corrosion of Tjpnd Lrnings of Indian Tea Chests. [No. 3, 



find is in a memorandum published by Dr. Gr. Watt, on special duty with 

 the Revenue and Agricultural Department, Government of India, and 

 dated Simla, June 21st, 1884. Dr. Watt makes the following statement : — • 

 " My views on the subject of woods suitable for tea boxes are at variance 

 with the popular outcry against our Indian timbers as injuring the Indian 

 Teas." He also states he has observed the following curious facts : — " The 

 tea may be completely destroyed, and yet upon the most careful scrutiny 

 not a single opening can be detected in the lead. It is obvious that 

 until the lead is corroded any injurious influence which the timber might 

 exert upon the tea could not take place." Again, " I have on several 

 occasions had the pleasure of inspecting lead said to have been corroded 

 by the action of the wood. But it is a curious fact that the action 

 seems to commence on the inside of the lead instead of on the outside or 

 on the surface in contact with the wood, (the supposed acid influence 

 which decomposes the metal) has not been apparently observed." He 

 also suggests " it may be the tea itself which corrodes the metal and not 

 the wood." 



Dr. Watt also during the Calcutta International Exhibition had an 

 opportunity of working with 200 tea- box woods from all parts of India, 

 and performed a large series of experiments on the action of these woods 

 on tea-lead. He says both unseasoned and seasoned woods were used in 

 these experiments, which were repeated once or twice, with moistened 

 woods and under conditions intended to simulate those of the hold 

 of a ship, and " in no instance has the lead been found to be in ever so 

 slight a degree chemically acted on;" and finally Dr. Watt states "he 

 failed utterly to discover any wood which seemed to possess the least 

 chemical action upon lead." 



In reply to this memorandum, Mr. Playfair, in the Indian Daily 

 Kews of July 29th, 1884, gave the results of certain investigations on this 

 subject, which had been made for him in London in 1883 by the late Dr. 

 A. Voelcker, F. R. S. Dr. Voelcker's conclusions were that " the corro- 

 sion of the lead (in the Indian tea-chests) unquestionably is due to the 

 attack of acetic or other volatile acids, and the subsequent formation of 

 white lead (carbonate of lead) by the action of the air. Considering the 

 fact that the surfaces of the leads which were in contact with the tea 

 were quite bright and sound, whilst the under surfaces in contact 

 with the wood were more or less corroded ; it appears to me that in all 

 probability green or unripe wood has been employed in making the tea- 

 chests. Such wood is known to generate in a somewhat warm locality 

 acetic and analogous organic acids which act upon lead." 



Dr. Watt, in a long letter, dated August 13th, 1884, also to the Indian 

 Daily News, discusses Dr. Voelcker's conclasions, and to a great extent 



