One more word before I close. The governments and private individuals in Europe cultivate and raise trees for both lumber and bark purposes. The forests are excellently cared for by efficient foresters, and the result is that the tanners obtain much cleaner and better bark, and of a very even quality. Would it not be a good idea if some individual, who would certainly earn the everlasting gratefulness of the tanners, would look into this matter, and see that not only the lumber side of our forest cultivation is not neglected, but that the bark also is preserved and cared for? Of course, we can obtain all the bark necessary at present and for some time to come, but the time will come when we shall certainly regret not having taken these steps, if the lumbermen and bark peelers go on devastating magnificent forests. Below will be found a table of weight results. Sole leather tanned with these materials gives for every 100 lb. green hide the following quantities of finished leather: lb. Oak bark 48 to 54 " extract 55 to 56 Pine bark 44 to 46 " extract 48 to 50 Willow 45 to 46 Birch bark and oak extract 49 to 51 Quebracho wood and extract 48 to 49 Valonia 52 to 56 Knoppern 51 to 53 Myrabolams 50 Knoppern, myrabolams and valonia 52 to 53 Hemlock 55 Specification of tanning materials used in different countries: _France_. Oak bark (kirmess). Sumac. Chestnut wood extract. Quebracho " " Some gambier. _Italy_. Oak bark. Pine " Sumac. Valonia. _England_. Oak bark. Divi divi. Myrabolams. Valonia. Mimosa. Extracts { Oak bark and wood hemlock. Gambier. Cutch. _Germany and Austria_. Oak bark. Pine " Willow bark. Valonia. Knoppern. Myrabolams. { Oak bark and wood. Extracts { Pine bark and wood. _Russia._ Birch bark. Willow " Oak " Pine " Hemlock extract. _Norway and Sweden_. Birch bark. Willow " Oak " WALTER J. SALOMON. --_Shoe and Leather Reporter_. * * * * * AN APPARATUS FOR HEATING SUBSTANCES IN GLASS TUBES UNDER PRESSURE.[1] [Footnote 1: Read at the meeting of the Chemical Section of the Franklin Institute held March 17, 1891.] By H. PEMBERTON, Jr. Chemists who do not happen to have in their laboratories oil or air baths for heating closed tubes can make an air bath at short notice from materials furnished by all dealers in steam fittings. _Order_: