836 JOURNAL OF FORESTRY 



sin" were obtained for the Forest Products Laboratory. If this is the- 

 case, the strength tests there made are indicative of commercial "rock 

 elm," and not of the botanical "rock" or "cork" elm (Ulmus race- 

 mosa). It would be well to ascertain whether samples of twigs were 

 sent along with the wood specimens tested. 



Sand Bags of Paper 



H. R. Christie, formerly of the British Columbia Forest Service, has 

 sent to an Ottawa friend a sample of the German sand bags made en- 

 tirely of paper fibers. In appearance the article somewhat resembles 

 a coarse, brown linen bag, but is smoother in finish, each strand being 

 tightly rolled and woven with great exactness. Mr. Christie states that 

 the bags are very serviceable except when exposed to moisture, when 

 they rot. The Germans, he reports, do not use nearly as many sand 

 bags as the British and French, for the reason that they have more 

 timber at their disposal and make prolific use of it. — Extract from' 

 Canadian Forestry Journal, September, 1917, p. 1300. 



The Yol'nglove Log Rule 



In "Forestry Quarterly," Vol. XII, No. 3, there is an article by Mr. 

 W. W. Colton on the Younglove log rule, in which he gives a history 

 of this log rule, at one time widely used in Massachusetts, but now 

 little known. He states that the basis of this rule is unknown, but be- 

 lieved to be based on a mathematical formula checked vip by mill stud- 

 ies. He states that since the death of the inventor, Tyler Younglove, 

 no more calipers have been made, and that the pair which he purchased 

 in a Fitchburg (Mass.) hardware store was probably the last pair on 

 sale. 



The writer has just purchased a caliper rule made by a Mr. Laurence 

 Watts, of Melrose, Alass., which he claims is the Younglove rule. Com- 

 paring this rule with the Massachusetts and Margolin log rules, it is 

 found to resemble them very closely, and it is evident that it is for use 

 under the same conditions, namely, for pine logs sawed into round- 

 edge box lumber with a small percentage of square-edge material. The 

 "Massachusetts" scale is a mill tally log rule constructed from data 

 collected by the Massachusetts forestry department at portable sawmills 

 in different sections of the State. The "Margolin" rule is a similar 

 scale constructed from data collected by Margolin and Lyford in south- 

 ern New Hampshire and published in the report of the New Hampshire 



