1903.] KOENIG—ARTIFICIAL PRODUCTION OF CRYSTALS. 225 
and full-faced crystals were never obtained. The largest crystals 
of the tabular habitus 4-5 millim. with prismatic and pyramidal 
faces well developed, but striated, so that they did not serve for 
measurements, were grown in a twenty-four-hour experiment. The 
crystals are fast to the asbestos of the plug P. 
c. Experiment made January 14, 190. 
inch copper wire two and one-half inches long was wrapped at one 
end with asbestos cord so as to form a plug which would support 
the wire within the incubator in a central position, thus giving a 
chance for free growth in all directions. At the end of fourteen 
hours the wire had been modified as shown in Fig. 5. The result 
was unexpected, probably owing to the change of current in the 
2arly morning, when the dynamo current had replaced the storage 
battery and the temperature had risen beyond the intended point. 
A piece of one-fourth 
Fig 5 
It is, however, all the more instructive, although a failure of the 
intention. Exceptionally large and fine crystals were expected to 
form by the arrangement, hence the failure. Instead seven distinct 
zones appeared, each telling a different story. Zone 1st(a@). The 
end of the wire nearest to the asbestos plug and the arsenic and 
in the centre of the heated field is completely fused, showing a 
lead-gray color and dull compared to its neighbor. The end is 
deeply converted into arsenide and this has been fused. Zone 
2d (6). Bright gray of the color of antimony, a jumble of crystal- 
line faces, but no crystals, has been partly fused. Zone 3d (c). 
A narrow strip of small but well-formed crystals, which belong to 
