CONTENTS. 



Department Bulletin No. 676. — The Relation of the Shrinkage and 



Strength Properties of Wood to its Specific Gravity: Page. 



Purpose 1 



•Specieg-locality averages 6 



Determination of specific gravity 6 



Moisture content of test specimens • 6 



The equations 7 



Application of the equations 9 



Appendix: Method of deriving equations 10 



Department Bulletin No. 677. — Soils of Southern New Jersey and Their 

 Uses: 



Character of the region 1 



General view of the soil-crop relations of Southern New Jersey. 9 



Detailed soil and crop maps 14 



Soil and crop survey of the Freehold area 16 



Soil and crop survey of the Hartford area 25 



Soil and crop survey of the Thorofare area -34 



"Soil and crop survey of the Swedesboro area 42 



Comparison of the detailed areas 54 



Freehold and Swedesboro areas contrasted 55 



Hartford and Thorofare areas contrasted 56 



Relation of soils to crop uses in the detailed areas 57 



Relationship between special crops and definite soil types in the detailed 



areas 61 



Soil preferences expressed by farmers 65 



Comparison of expressed preferences with results of surveys 70 



Soil and crop geography : 72 



Review of soil uses by series, classes, and types of soils 72 



Conclusions 76 



Department Bulletin No. 678. — Influence of a City on Farming: 



Object and results , 1 



General conditions 2 



Seasonal distribution of labor required by crops 7 



Description of farm practice ' 10 



Relation of distance from city to type of farming 11 



A comparative study of types of farms 14 



Description of several farms illustrating types found in this section 18 



Department Bulletin No. 679. — The Application of Optical Methods 

 OF Identification to Alkaloids and Other Organic Compounds: 



Optical properties in the identification of synthetic crystalline substances. 1 

 Methods for determination of optical constants: 



Apparatus 2 



Observations 3 



Measuring the optical properties of an alkaloid 8 



Summary : 9 



Department Bulletin No. 680. — Miscellaneous Conifers of the Rocky 

 Mountain Region: 



Scope of bulletin 1 



Generic characteristics of larches 2 



Generic characteristics of hemlocks 11 



Generic characteristics of false hemlocks "- 19 



Generic characteristics of incense cedars 27 



Generic characteristics of arborvitaes — ' ' cedars " 32 



Family relationships of yew trees 39 



Generic characteristics of yew trees 40 



Key to genera and species 44 



List of publications on forest trees : - - -• 45 



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