BY JAMES TOLSON, ESQ. gps 
Table 7.—Showing the value of C or the conducting powers of the 
materials, being the quantity of heat, in units, transmitted 
per square foot per hour by a plate 1 inch thick, the two 
surfaces differing in temperature 1°. From the experiment 
by” Beclet:* 
Value of C. 
Copper 2: ee Le’ ie 403 Ta-15 BS. 
Iron aie Sis ate =e =e ste ZN 
Zinc sas 5 sas aoe S48 sid |p Bei 
ECAC oe aa ee nite $a 9 AEE 
Stone, fine calcareous 34 a she ee 16°7 
Stone, ordinary... oe us ae ai STOO 
Glass’ Jen se 6 
Baked Clay, brickwork Ass ae 4°83 
Plaster, ordinary ae see 3°86 
Fir W ood, perpendicular to the fibre ... a 748 
Fir Wood, parallel to the fibre Hf ar esr 
Gutta yPercha: 5. He ee ate ae 1°38 
Indiarubber _... a bis See aA 137 
Brickdust, sifted woh Pa wih a 1°39 
Coke, pulverised ae sis ee Se WZ 
Conk <2. oe a ae Pe 1 i 
Chalk, in pow der x ae = ae "869 
Charcoal of Wool, in powder . ee ce Ae "636 
Straw, chopped... sa ee ie re 563 
Coal, small sifted roe A me Lee "547 
Wood ashes _... ae ae Bein see my gi 
Mahogany dust ae a mr #; "523 
Canvas of Hemp, new ae dn ane "418 
Calico, new |. i: mt oe = bie “402 
Writing Paper, white ... we ss "346 
Cotton. Wool and Sheep W ool. es oe a 1223 
Hair, felt Ser ner oes sat cet "293 
Blotting Paper, grey... ae oe one "274 
iWeat! Oy. ca re ae te he 53 
Oil os Rie aie ae aoe a 14°5 
Water, at ieee ee : ae ak 5°316 
Do., mean between 95° and 32° ore ar 6°6 
ice..at 32° : 2°64 
Having thus evoan ihe a of ie Arce elements, R, 
A, and c we will now endeavour to apply them to a 
building artificially cooled for the purpose of refrigeration. 
* Mr. Coleman (of Messrs. Bell, Coleman and Co.), as the result of a 
series of experiments instituted by him, has ascertained the following 
