MICHIGAN ROADS AND FORESTS 





Town Roads Need 



Heavier Construction 



(Continued from page 3) 



writer submits that they are not materially 

 reduced in their proportions, except, possibly 

 by prolcnged firing which is seldom done, 

 owing to the loss of time and the expense. 



Refine'd tar is superior for road works, as 

 the water and light oils have been extracted 

 by effective distillation. Its quality is more 

 uniform and reliable. It will net foam over 

 when boiled, nor will it tend to peel off dry 

 stone surfaces if it is applied hot. It also 

 adheres better and is more durable. If the 

 naphthalene and anthracene, which are crys- 

 tals possessing no binding properties, are also 

 extracted and the dead cils returned to the 

 still, the refined tar will be further improved. 

 The tar distillers will have also extracted 

 the most valuable and remunerative products, 

 and thus permit the refined tar to be sold at 

 a low rate. 



The percentage of free carbon contained in 

 the tar increases with higher temperatures of 

 the retorts and in some modern gas works 

 one-third of the pitch obtained by the distilla- 

 tion of tar consists of free carbon, which has 

 no binding qualities necessary for road works. 

 The specific gravity of crude tar is largely 

 controlled by the proportion of free carbon 

 it contains; that crude tar is thick and viscous, 

 is therefore not a true indication of its value. 

 Before old road surfaces are tarred, they 

 must be even and in good condition, and free 

 from pot holes. The dust should be remov- 

 ed by energetic brushing, and the joints ex- 

 posed as much as possible. The mad should 

 be dry and warm; damp surfaces prevent the 

 tar and reduce its penetrative powers. The 

 drier and warmer the surface, the more it 

 will absorb liquids, capillary attraction being 

 probably more pronounced, and the material is 

 hungry and thirsty. 



The tar can be distributed by hand or spray- 

 ed by machine. In the former process the 

 temperature of the tar is, perhaps, under bet- 

 ter control, and advantage can be taken of 

 local climatic conditions, but it is slow, whilst 

 the machine is able to cover a large area in 

 a minimum of time. In either case, the tar 

 should be given ample time to soak into the 

 surface, to assist which and also to prevent 

 pending and streaming, squeegees or brushes 

 should be energetically used. The traffic 

 should be diverted, so that the newly tarred 

 road is not disturbed, until a durable and 

 plastic skin has been formed. 



The use of grit, dust, or chippings does not 

 seem warranted, especially immediately after 

 the road has been tarred for the tar should 

 be allowed to sink into the surface rather than 

 be retained on the top. The sand, grit or 

 shippings, if used at all, should be evenly and 

 frugally spread. Tarring of roads on wet 

 subsoil and having no efficient under-drainage 

 is almost useless. 



Tarring of newly macadamized roads is pre- 

 ferable, as the joints are then more open, per- 

 mitting the tar to get in between the stones 

 x and thereby to become a true binder, and if 

 the voids have been reduced by a rational 

 proportion of small stones, the coating and 

 metal will become more solid and the dur- 

 ability of the work extended. 



The methods of testing the materials used 

 on roads cannot be dealt with in a short com- 

 munication, but it is nevertheless an import- 

 ant matter and merits a more general consid- 

 eration and adoption. 



The construction and maintenance of up-to- 

 date roads require careful selection and scien- 

 tific employment cf siutable materials, and this 

 desirable consummation can only be achieved 

 by the aid of science and experience, hence 

 the need for a fuller and more concentrated 

 effort in this direction. 



THE 



PORT HURON 



GENERAL 



PURPOSE 



ROLLER 



PORT HURON ENGINE & THRESHER CO., 



"WRITE US" 



FOR 

 CATALOGUE 



PORT HURON, MICH. 



ASK 

 THE 

 USER 



The Milling & Power Company has installed 

 a 35-h. p. electric motor in the Marten & Eck- 

 man Lumber & Timber Company saw mill at 

 Cassopolis, to operate the large saws. 



ENLARGES PLANT. 



The addition to the boiler shops of the J. I. 

 Case Threshing Machine Co., Incorporated, 

 Racine, Wisconsin, is about completed. This 

 is a building 60 ft. by 215 ft., which will be 

 used exclusively for a stock room for the Case 

 boiler shops. A boiler storage has been com- 

 pleted 230 ft. by 60 ft. This is equipped with 

 a traveling train for movement of boilers 

 from one part of the building to another. 



Under the supervision of the Case architect 

 the above work has been undertaken and 

 completed, also the remodeling of the Gar- 

 field warehouse, which is 100 ft. by 250 ft. 

 and two storjes high. This building, when 

 the remodeling is completed, will be used as 

 a machine shop. Machine shop facilities have 

 not been adequate. 



As soon as the weather will permit, other 

 buildings will be put under construction and 

 completed. The heavy business for the pres- 

 ent year has necessitated all these changes. 



BERLIN PRESERVES FORESTS. 



The determination of Berlin's municipal au- 

 thorities to make their city the model of what 

 a metropolis ought to be is demonstrated 

 afresh by their intention to maintain the fine 

 forests which surround it. 



Busy as they are with the problem of re- 

 lieving street congestion and providing suit- 

 able lines of transportation for the rapidly 

 increasing population, they have found time 

 to conclude negotiations with the government 

 for the purchase of seven forests situated at 

 various points about the city and covering in 

 all something less than 40,000 acres. 



The price paid, about $45,000,000, is large, 

 but in fact works out at just under half a dol- 

 lar a square yard. Nearly all the purchased 

 forests, including those of Grunewald, Tegel, 

 Grunau and Potsdam, are favorite haunts of 

 the Berliners and well known to American 

 and English visitors. 



