90 
POPULAR SCIEI^CE l^J-EWS. 
[June, 1891. 
for the night. I was desirous of observing their 
ascension in the morning," he adds, " but, having 
to set off before day, I had not that gratification." 
rOriginal In POPULAR Science News.] 
NOTES OX CANADIAN CHRYSOTILE. 
BY A. II. FERGUSON. 
Most students of mineralogy are aware that the 
"asbestus" wliicli occurs so plentifully in this 
province, and in Italy, is not asbestus — in the 
mineralogical sense of the word — at all, but is 
simply chrysotile, or a fibrous variety of serpen- 
tine. The true asbestus is a fibrous variety of 
hornblende, or amphibole. It contains no water, 
whereas chrysotile contains 12 to 14 per cent. 
Chrysotile, then, is a hydrous silicate of magne- 
sia. It is colored pale greenish white to deeper 
shades of green, also yellowish and brownish.* 
There exists, however, a variety of Laurentian 
"asbestus," from Templeton, Canada, which is 
perfectly white, not a trace of green or brown 
color being discernible. The Italian chrysotile is 
also more frequently white than the Canadian, 
but is almost perfectly dull, lacking entirely the 
beautiful silky luster of the Canadian mineral. 
The fibers of chrysotile are delicate and easily 
separable. The best fiber is soft and silky, but 
some is harsh and rather brittle. Indeed, there 
may be noticed a regular and gradual gradation 
in harshness from the fibrous variety of serpen- 
tine called picrolite, through all intermediate 
stages, down to the most pliable and silky amian- 
thus. Speaking now of chrysotile itself, it is 
noticeable that its harshness seems to depend, in 
a measure, upon tlie percentage of water which it 
contains. t Thus, in some very short and harsh 
fiber, the water was found to l>e as low as 12.7 to 
even 12.2 per cent., while in fiber of good quality 
no lower percentage than 13.4 has been found. 
By ignition in a crucible the water is driven off 
from chrysotile. The remaining body retains its 
original flljrous form, but is found to possess a 
brown color, the depth of which is due to the 
amount of iron present in the sample.* Even the 
purest white "asbestus" takes a more or less yel- 
lowish color on ignition. 
By the ignition, also, the fiber becomes harsh, 
and can now be crumbled to a powder between 
the fingers. This fact offers itself to advantage 
when we wish to make an analysis of the mineral. 
Before ignition the slippery fiber cannot be rubbed 
to powder without a vast expenditure of time and 
"elbow-grease." But, if we first drive off the 
water by ignition, the operation of grinding may 
be easily and rapidly done. The snuft'-colored 
powder thus obtained is decomposed with the 
greatest ease by fusion with sodium carbonate. 
As assistant to Prof. J. T. Donald, the writer has 
had occasion to analy«i several samples of Cana- 
dian "asbestus" from various localities. The 
mean of these analyses gives the following as 
its composition : 
Silica 40.7 per cent. 
Magnesia 42.1 " 
Ferrous oxide 1.6 " 
Alumina 1.8 " 
Water 13.8 " 
100.0 
The presence of alumina is thus placed beyond 
doubt. It was found in every case, the amount 
ranging from 0.9 to 3.6 per cent. An analysis of 
a specimen of Italian chrysotile shows that it 
agrees perfectly in composition with the Canadian 
mineral. 
• E. S. Dana, Text-Book of Mineralogy, 14tli edition, p. 350. 
t J. T. Donald, "Notes on Asbestus and Some Associated 
Minerals," Canadian Jtecord of Science, Vol. IV., No. 2, 
April, 1890, p. 101. 
As to the action of acids on chrysotile, Dana* 
says that it is decomposed by hydrochloric and 
sulphuric acids, the silica being left in flue fibers. 
I have found that if finely-teased chrysotile be 
boiled with hydrochloric acid, the iron is quickly 
and completely removed, the remaining substance 
being perfectly white in color. The remaining 
silicate of magnesia is but slowly decomposed on 
continued boiling. Sulphuric acid has even less 
action than hydrochloric. Cold acids have but 
little or no effect on the mineral. 
The above facts lend themselves readily to the 
utilization of "asbestus" fiber for filtering pur- 
poses. We boil the finely-teaSed fiber for about 
five minutes with hydrochloric acid. By now 
washing the pulp with water, and packing in the 
throat of a funnel, we obtain an excellent medium 
for the filtration of such solutions as are too 
strongly acid to allow of their filtration through 
paper. 
By first igniting the "asbestus" fiber, and then 
grinding finely, we find that it is mwjh more rap- 
idly acted upon by boiling hydrochloric acid ; so 
rapidly, indeed, that I have no doubt the mineral 
could be decomposed for analysis in this way. I 
have hitherto, however, preferred to fuse the fine 
powder with sodium carbonate, as I fancy the 
silica thus obtained will be purer than that ob- 
tained by simple solution in hydrochloric acid smd 
evaporation. I intend, later, to compare the two 
methods, and, if the results obtained are of any 
value, I shall be happy to communicate them. 
*E. S. Dana, Text-Book of Mineralogy, lith edition,]). 350. 
«♦> 
[Specially Observed for Popular Science News.] 
METEOROLOGY FOR APRIL, 1891. 
TEMPERATURE. 
Average Thermometer. 
At 7 A.M. . . 
At 2 P.M. . . 
At 9 P.M. . . 
Whole month . 
Second average 
Last 21 Aprils . 
Second average 
43.93° 
57.23° 
45.63° 
48.93° 
48.11° 
45.21° 
44.65° 
Lowest. 
37° 
28° 
28° 
Highest. 
63° 
76° 
67° 
76° 
76° 
Range. 
35° 
39° 
35° 
48° 
48° 
i 38.17° I 50.61° 
! in 1874. in 1878. 
37.71° 
60.01° 
12.44° 
12.30° 
The lowest point reached by the mercury the 
last month was 28°, on the 6th, and this was also 
the coldest day, averaging 34.66*^ ; the 5th and 7th 
averaged 35'-" each. The first week was quite cool, 
ranging from 28° to 46" at the hours of observa- 
tion. The highest point in the month was 76°, on 
the 14th and 30th. The 22d was the warmest day, 
at 65°. Several other days reached 62° and up- 
wards. The entire month was 3.72° above tlie 
average in twenty-one Aprils, and has been ex- 
ceeded but twice in this period, viz., in 1878 and 
1886. The coldest point in these twenty-one 
Aprils was 19°, in 1874, and the warmest 83°, in 
1885. The mean temperature siiice January 1 has 
been 35.76° ; but the mean for these four months 
in twenty-one years has been only 32.20°, or 3.56° 
warmer this year than usual, causing the season 
to be ten or twelve daj'S in advance of the average. 
Each month this year has been from 1° to 5° above 
the average, giving a surplus of 427.2° of unusual 
heat. 
SKY. 
The face of the sky, in 90 observations, gave 53 
fair, 15 cloudy, 18 overcast, 3 rainy, and 1 snowy, 
—a percentage of 58.8 fair. The average fair the 
last twenty-one Aprils has been 52.4, witli ex- 
tremes of 32.2 in 1878, and 70.0 in 1872 and 1890. 
The 16th was foggy in the morning, and the even- 
ing of the 18th was attended with sharp lightning 
and one-tenth inch of rain. There were several 
fine days, especially the 5th, 13th, and 20th to the 
22d. 
PRECIPITATION. 
The amount of precipitation the last month, in- 
cluding half an inch of melted snow, was 4.91 
inches. This was mostly on the 3d — a heavy 
rainfall of 3.40 inches, mingled at times with 
snow. On the 11th and 15th .72 inch and .61 inch 
fell, leaving one-half the month almost entirely 
destitute of rain, which is now much needed, 
especially to secure a good hay crop. The aver- 
age amount of precipitation the last twenty-three 
Aprils has been 3.91 inches, with extremes of 1.70 
in 1886, and 8.50 in 1870. The amount since Jan- 
uary 1 is very large, being 27.98 inches, while the , 
average for these four months in twenty-three j 
years has been only 19.41 inches. 
PRESSURE. 
The average pressure the past month was 29.935 
inches, with extremes of 29.12 on the 3d, and 
30.45 on the 9th and 10th, — a large range of 1.33 
inch. The mean for the last eighteen Aprils has 
been 29.906 inches, with extremes of 29.767 in 
1884, and 30.078 in 1886,— a range of .311 inch. 
The sum of the daily variations was 5.81 inches, 
giving a mean daily movement of .194 inch. This 
average the last eighteen Aprils has been .179, 
with extremes of .139 and .239. 'ITie largest daily 
movements were .98 on the 3d, and .51 on the 22d. 
The movement on the 3d was remarkable, nearly 
one inch in twenty-four hours, the mercury then 
standing at 29.12°. It continued to fall after the 
hour of observation till it reached 28.90 — a fall of 
1.20 inches in about twenty-seven hours! The 
occasions are quite rare when the pressure falls 
below 29 inches. 
WINDS. 
The average direction of the wind the past 
month was W. 18° 48' N., while the mean for the 
last twenty-two Aprils has been W. 39° 22' N.,- 
showing less northerly winds than usual in April. 
The extremes in twenty-two Aprils have been 
E. 15° 0' N. in 1877, and W. 9° 35' S. in 1880,— a 
wide and quite uncommon range of 174° 35', or 
nearly a whole semi-circle. The relative progres- 
sive distance travelled by the winds the past 
month was 49.65 units, and during the last twenty- 
two Aprils 728.2 such units, an average of 33.10, — 
showing less easterly winds the present April 
than usual. Being less northerly, also, contrib- 
uted to the high temperature of the month. 
.D. W. 
Natick, May 5, 1891. 
[Specially Computed for Popular Science News.] 
ASTRONOMICAL PHENOMENA FOR JUNE, 
1891. 
The sun reaches its greatest northern declina- 
tion and summer begins about noon June 21. 
There will be an eclipse of the sun on the morn- 
ing of June 6, invisible in the eastern part of the 
United States, but it may be seen as a partial 
eclipse west of a line running from Lake Erie to 
Texas. At Chicago it begins at 9h. 12m. A. M., 
Cential Standard time, and lasts about twenty-five 
minutes. As the apparent diameter of the moon 
is less than that of the sun, the eclipse will not be 
total at any place on the earth, but it will be 
annular in the Arctic Ocean north of Siberia. 
Mercury is at greatest western elongation on 
the morning of June 5, but it is too far south to 
be easily seen. Venus is still a morning star, but 
is gradually getting nearer the sun. It rises' 
about an hour and a half before the sun. The 
