COCKLES 265 



or quite at the mouth of estuaries far away from sources of sewage 

 contamination." The experience at Leigh-on-Sea, Southend, and 

 other places seems to tell a different tale, and it is evident that 

 the shell-fish may be grown on polluted beds. After growth, it is 

 true, they are raked into hand-nets, and taken to the cockle-sheds, 

 and here are plunged into coppers of boiling water in the nets, after 

 which they are riddled through wide-meshed sieves, which allow 

 the soft parts to pass through, retaining the shells, which are 

 deposited in heaps for sale to oyster cultivators. The cockles them- 

 selves are then washed in about five changes of water, to the last 

 of which a certain quantity of salt is added. Not infrequently, the 

 same water is used in all the washings. The so-called boiling is 

 evidently misleading. Though the water is actually at the boiling 

 point, the cockles are plunged in in a mass, and for a short time, 

 and it by no means follows that every part is exposed to a tempera- 

 ture of 212 F. 



Dr Klein has shown that the usual method of cooking only 

 amounts to scalding, and cannot be relied on to sterilise micro- 

 organisms. The live fish, with shells tightly closed, are held in a 

 net and plunged en masse into a vessel containing boiling water. 

 The immersion of the cold mass immediately lowers the tempera- 

 ture, and when in the course of two or three minutes it begins to 

 boil again, the net is lifted out. The scalding kills the fish and 

 causes the shells to open, but it does not sterilise the contents. 

 Dr Klein found that the temperature of the water fell, on the im- 

 mersion of the fish, from 100 C. to 65 ; and that cooking for the 

 usual time was totally inadequate to kill the micro-organisms. Fish 

 that had been kept in typhoid polluted water were tested, and were 

 found to be swarming with live bacilli after cooking. Prolonged 

 boiling would, no doubt, be effective, but it causes the fish to 

 shrivel up and spoils them for sale. 



Dr Klein then suggested that cooking by steam might be found 

 an efficient steriliser without spoiling the fish as food. It is well 

 established that current steam is much more penetrating than 

 boiling water for purposes of disinfection, and it is always used in 

 preference. The question was whether an exposure sufficient to 

 sterilise would amount to over-cooking, and recent experiments 

 carried out in the kitchen at Fishmongers' Hall were intended to 

 settle that point. Cockles and mussels were cooked in a steamer 

 under the direction of Dr Klein in the presence of several repre- 

 sentatives of the trade, who examined them afterwards. Two 

 batches were cooked, one for ten minutes and the other for five. 

 The steamer used was a fixed vessel some 2 feet deep, into which 

 steam is introduced by a pipe about an inch from the bottom. A 

 layer of cockles was placed at the bottom, and two other layers on 



