BEYIEWS — AGEICULTtEE OP ME EEENCH EXHIBITION. 145 



economic botanist, no less than an object of commercial interest to the merchants 

 and artificers of Europe. Such a large collection of specimens offered an excellent 

 opportunity for testing their comparative value for different purposes of construc- 

 tion ; and a series of experiments were carried out, the results of which, I have no 

 doubt, will materially add to our knowledge of the relative strength of materials. 

 The importance of these experiments would probably be more readily seen in 

 reference to shipbuilding than to any other ordinary purpose for which wood in 

 large quantities is required. In shipbuilding about 40 cubic feet (using round num- 

 bers) are required per ton, — say 32 cubic feet for the hull, and 8 cubic feet for 

 fittings,— this would give for a ship of 1000 tons 32,000 + 8000 cubic feet. The 

 two important elements for the consideration of the builder are strength and specific 

 gravity, — both separately and in relation to each other. The value of the former 

 is nc/t so generally determined as that of the latter; indeed this formed the prin- 

 cipal o'>ject of the experiment alluded to ; let us see, then, how far the latter 

 element of the physical character of timber influences the ship. The first-class 

 woods entered at Lloyd's are eight in number — English oak, American oak, African 

 oak, Morung Saul, East India teak, Greeuheart, Mora, Iron bark ; these mostly differ 

 considerably in specific gravity. A cubic foot of English oak weighs 40 lbs. ; of 

 American oak, 46 lbs. ; of African oak, 50 lbs. ; of Malabar teak, 39 lbs. ; of Mora 

 excelsa, 62 lbs.; of Iron bark, 65 lbs. Besides these, other woods are largely used, 

 as Honduras mahogany, which weighs 31 lbs. per cubic foot ; Eucalyptus, 50 lbs. ; 

 Canada pine, 22 lbs. ; and cedar, 25 lbs. 



".Now, taking these specific gravities into calculation, the hull of a 1000-ton 

 ship would require of English oak, 572 tons ; of American oak, 657 tons ; of Afri- 

 can oak, 734 tons; of teak, 537 tons; of Mora, 885 tons; of Eucalyptus, 714 

 tons, and of Iron bark no less than 930 tons ; while it would only require of 

 Mahogany, 443 tons; of Canada pine, 316 tons; or of Cedar, 362 tons. 

 Taking the two extremes, Iron bark and Canada pine, a difference is shown of 

 614 tons — nearly 200 per cent.— in the displacement tonnage of the vessel, and 

 consequent increased capacity for freight. 



" These collections contained also many woods valuable for furniture and orna- 

 mental purposes, — the black walnut of Canada, for instance, of which a suite of 

 drawing room furniture was shown ; the Dacrydium Franklinii, or Huon pine of 

 Tasmania, whose fragrant odour and brilliant golden color attracted much notice. 

 In the Algerian collection were pome fine timber woods, and also some beautiful 

 specimens of the Thuja articulala, whose richly marked, deep tinted knots found a 

 ready sale in Paris at the rate of 2s. per lb. weight. The specimens of Amboyna 

 wood in the Dutch collection were remarkably beautiful. One piece was valued at 

 1200 francs." 



The spirit of the author's concluding observations will find a ready 

 response among the true hearted of our race, not only in Canada, but 

 in every civilised nation of the earth : 



" This brief sketch which I have given you has touched but the surface — the 

 salient points of interest which naturally present themselves to the ordinary ob- 

 server. But a man cannot long remain an ordinary observer "whose duties lead 

 him, day by day, and week by week, to the examination of these great and varied 

 evidences of Divine beneficence. He cannot compare unmoved the productive 

 ratio of skilled and Christian Europe with that of the dark, unevangelized nations 



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