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someness and expense of preparing anhydrous iodide 
of calcium, which, like chloride of magnesium, is apt to 
undergo partial decomposition during ignition — and it must 
he remembered that partial decomposition of iodide of 
calcium involves the formation of lime, a substance practically 
infusible, which, during the reaction with sodium, must 
prevent, if present, the aggregation of the minute particles of 
reduced calcium into globules. In order to overcome this, 
and the before-named objection to the process, the author 
fuses together equivalent quantities of iodide of potassium 
and of chloride of calcium. The fused mass is poured into 
an iron crucible and covered till cool enough to handle ; the 
mass is then dropped out, and a rather less than an equivalent 
quantity of sodium is put into the crucible, and the mixture 
of calcium and potassium salts is placed above it. ' The 
crucible is then closely covered, and heated to redness. The 
heat need neither he strong nor long continued. The best 
results are obtained when the crucible cover is fastened down, 
but calcium in lump may be obtained without using more 
pressure than that afforded by a well fitting lid. The re- 
action does not appear to be violent, and hence the advantage 
of considerable pressure. Is the slight violence of the re- 
action between sodium and the calcium salt owing to the 
near approach of the two metals as to atomic weight, and 
thence specific heat? It is easier to obtain calcium in 
lump by the modification of Lies Bodart’s process, that I 
have described, in a small way, than it is to obtain magnesium 
in lump on a like scale. 
