itArr.j BKIQUETTI1SIG TESTS. 161 
tood rough handling, and they weighed on the average 6.30 pounds 
ach. 
This coal was briquetted with T per cent pitch B, using the high- 
st pressure obtainable. As received from the press, these briquettes 
rere somewhat plastic, but on cooling they proved to be brittle. They 
weighed on an average 7 pounds each. 
NEW MEXICO. 
New Mexico No. 1. — This black lignite was first briquetted with 12 
er cent pitch A, but the resultant briquettes were unsatisfactory in 
very way. Five and a half tons of this coal were briquetted with 
5.8 per cent pitch X, and the resultant briquettes were apparently 
ood in every way and could be handled very easily without any 
rumbling. On cooling, however, they began to crumble, nd they did 
ot stand the weather very well. In burning they showed a great 
mdency to disintegrate. 
This coal was tested on the English machine with 8 per cent pitch D. 
'he resultant briquettes were rather crumbly and earthy, and on cool- 
ig were covered with white efflorescence. They did not contain a 
ifficient quantity of pitch. They weighed on an average 6.83 pounds 
ich and had a specific gravity of 1.18. Their crushing strength was 
120 pounds to the square inch. 
As 8 per cent of pitch D did not give any excess of binder, and as 
te resultant briquettes were not satisfactory, another ton of this coal 
as tested with 10 per cent of pitch D. While the briquettes fresh 
om the machine were somewhat stronger than those with 8 per cent 
pitch D, it was found that upon standing and becoming thoroughly 
k)1 they became so like those made with 8 per cent pitch that they 
>uld not be distinguished from each other. This indicated that a 
tisfactory briquette could not be made with this pitch, even by 
eatly increasing the percentage. In making these briquettes, the 
iglish machine was run under ideal conditions, having a constant 
essure; the coal was sufficiently dry and not too tine, and could be 
iquetted at a moderate temperature. There was a little more white 
florescence on the briquettes with the 10 per cent than with the 8 
[r cent pitch D, although the briquettes were quite glossy. The 
erage weight of these briquettes was 6.42 pounds each and their 
ecific gravity was 1.02. The crushing strength of these was 5,900 
unds per square inch, as compared with 7,120 pounds per square 
s ?h for those made with 8 per cent pitch D. The eggettes were quite 
pssy on the surface, but had a dull fracture and were not very 
lacious. There was a tendency to disintegration in burning. 
I The most satisfactory test was with pitch II. and one ton of this coal 
s briquetted with 8 per cent of this pitch. The resultant briquettes 
Bull. L'<>1— 05 11 
