318 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1909. 
these were put into blast before January 1, 1905, at which time 832 new ovens 
were in course of construction. At the close of 1905 there were only 417 new 
ovens building, and at the close of 1906 new work was limited to 112 Otto- 
Hoffmann ovens, which were being added to the 260 ovens already built at 
Johnstown, Pennsylvania, by the Cambria Steel Company. These new ovens 
were completed and put in blast in February, 1907. 
This condition is somewhat difficult to understand when the economies effected 
by the use of retort ovens have been so clearly demonstrated. These economies 
consist not only in the higher yield of coal in coke, but in the recovery of the 
valuable by-products of gas, tar, and ammonia. One of the reasons that has 
been assigned for the comparatively retrogressive condition exhibited by the 
statistics for 1905 and 1906 (comparison being made with beehive oven construc- 
tion, 5,893 new beehive ovens having been completed in 1906, with 4,407 building 
at the close of the year) is the lack of a profitable market for coal tar, and yet 
the United States is importing coal-tar products to the value of several million 
dollars annually, while the development of the fuel-briqueting industry has been 
held back because of the lack of assurance of a steady supply of coal-tar pitch 
for a binder, and users of creosoting oils for the preservation of timber complain 
of an insufficient domestic supply of this product of coal-tar distillation. 
The truth is that one branch of industry is so dependent upon 
another that there must be equal progress along the whole line of 
industrial life if complete recovery of all the available elements of 
our natural resources is to be effected. The chemical industry must 
keep pace with the mining and metallurgical industry. We may 
be moving too slowly in that direction, but we can distinguish a 
steady movement toward this needful cooperation. It is encourag- 
ing, for instance, to find that the waste gases from the furnaces of 
the Tennessee Copper Company are being turned into sulphuric acid 
for the manufacture from southern phosphates of the superphos- 
phates which the fertilizers of the southern cotton fields need. Fail- 
ing this mutual relation between the metallurgist of Tennessee and 
the chemical manufacturer, the blame should not rest entirely upon 
the metallurgist for wasting that for which, heretofore, he has been 
unable to find a market. The same justification exists abroad as in 
this country for similar waste in other branches of industrial activity. 
It is nevertheless true that legal compulsion alone has driven 
manufacturers to introduce improvements and economies which were 
demanded by public safety, and which have redounded to the benefit 
of the reluctant corporations. In Germany and England the disposal 
of noxious vapors and noxious liquors has been required of the 
manufacturers, but their compulsory removal from the atmosphere 
and the water has resulted in their conversion into useful products, 
and the building up of new technical industries. An agitation is 
springing up in the West against the fumes from smelting works 
being turned loose into the atmosphere. While in some cases the ~ 
injury done to vegetation may have been falsely attributed to the 
smoke from metallurgical works, the agitation has been followed 
