118 JAMES CLERK MAXWELL. [CHAP. V. 



I have regularly set up shop now above the wash-house at 

 the gate, in a garret. l I have an old door set on two 

 barrels, and two chairs, of which one is safe, and a skylight 

 above, which will slide up and down. 



On the door (or table), there is a lot of bowls, jugs, 

 plates, jam pigs, 2 etc., containing water, salt, soda, sulphuric 

 acid, blue vitriol, plumbago ore ; also broken glass, iron, and 

 copper wire, copper and zinc plate, bees' wax, sealing wax, 

 clay, rosin, charcoal, a lens, a Smee's Galvanic apparatus, and 

 a countless variety of little beetles, spiders, and wood lice, 

 which fall into the different liquids and poison themselves. 

 I intend to get up some more galvanism in jam pigs ; but I 

 must first copper the interiors of the pigs, so I am experi- 

 menting on the best methods of electrotyping. So I am 

 making copper seals with the device of a beetle. First, I 

 thought a beetle was a good conductor, so I embedded one 

 in wax (not at all cruel, because I slew him in boiling water 

 in which he never kicked), leaving his back out ; but he 

 would not do. Then I took a cast of him in sealing wax, 

 and pressed wax into the hollow, and black-leaded it with a 

 brush ; but neither would that do. So at last I took my 

 fingers and rubbed it, which I find the best way to use the 

 black lead. Then it coppered famously. I melt out the 

 wax with the lens, that being the cleanest way of getting a 

 strong heat, so I do most things with it that need heat. 

 To-day I astonished the natives as follows. I took a crystal 

 of blue vitriol and put the lens to it, and so drove off the 

 water, leaving a white powder. Then I did the same to 

 some washing soda, and mixed the two white powders 

 together ; and made a small native spit on them, w T hich 

 turned them green 3 by a mutual exchange, thus : 1. Sul- 

 phate of copper and carbonate of soda. 2. Sulphate of 

 soda and carbonate of copper (blue or green). 



With regard to electro-magnetism you may tell Bob that 

 I have not begun the machine he speaks of, being occupied 

 with better plans, one of which is rather down cast, however, 



1 In the " old house " (above, p. 26, 1, 4); now fitted up as a gun-room. 



2 i.e. Jars. 3 This is still remembered by " Lizzy," Mrs. MacGowan. 



