Cumming, Linnæus, b. 1843. [from old catalog] · New York, D. Van Nostrand · leaf 388
Fig. 238. 238. The Thermopile.—To still further increase thesensitiveness, a number of couples are arranged in compoundseries (Fig. 239, a), and are folded together as in Fig. 239, 6,to bring all the junctions of the same kind into a small area,generally in form a square. The instrument then forms…
Electricity
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