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nlar or sparry, which conceals the abdominal joints and 

 lobes, and exhibits only the relieved outline of the cast ; but 

 in a few, their structure is still discernible, as is well exem- 

 plified in a superb specimen, in the possession of Dr. James, 

 of Albany, in which, in fact, the greater part of this covering 

 has disappeared. The largest American asaph which I 

 have seen, is that of Dr. James." 



William Mayell read a paper on the processes used in 

 hat making. 



In this communication, the author, who is a practical 

 artisan, stated that the processes used by the hatter are me- 

 chanical and chemical. The former are similar in all coun- 

 tries, while the latter frequently vary. 



The operations included under the bead of mechanical 

 ones, viz. bowing, basoning and planking, were next describ- 

 ed. It was remarked, that vvuul and ilk' fur of different ani- 

 mals, possess in various degrees, the property of combining 

 by means of the hatters' processes, and in order to improve 

 this, several chemical operations are employed. The most 

 common of these, was the addition of wood ashes to the wa- 

 ter used in boiling. The alkali in this or similar substan- 

 ces aids in promoting the contraction or shrinking of the 

 hat, and upon the success of this, its fineness and firmness 

 depend. 



it is however, a very uncertain process, and workmen 

 frequently fail in it. Mr. Mayell is inclined to ascribe the 

 variety in this ease to a want of attention to the proportions 

 that have been found most effective. The quantities of sub- 

 stances containing either the vegetable or volatile alkali, 

 which are used in successful experiments, should be noted. 



Another difficulty attending the mechanical operations is 

 the danger of shrinking too much. « If the hats be not 

 well boiled, their texture will be loose, and it will be impos- 

 sible, perhaps to shrink them to the required size. On the 

 other hand, the boiling, aided by the wetting and rolling, 

 may cause too rapid a contraction, and yet, if the latter pro- 

 cesses be discontinued, the texture of the hats will be coarse 

 and harsh." 



To retard the shrinking, brewers' dregs are frequently 

 employed by some manufacturers, while others use them di- 

 rectly for it. The reason of this diversity of result is thus 

 explained : These dregs when fresh, contain a quantity of 

 mucilage and saccharine matter and little or no acid. Their 

 application will thus effect the first object. But if they 

 have stood a considerable time, fermentation has gone on, 

 and acetous acid in a greater or less degree, is produced. 



