May 9, 1884.] 
SCIENCE. 
585 
RECENT PROCEEDINGS OF SOITENTIFIC SOCIETIES. 
Chemical society, Washington. 
April 24. — Thomas Taylor presented a paper upon 
oleomargarine, butter, and butterine, in which he 
described methods for the recognition of imitation- 
butter by means of the microscope, polariscope, and 
sulphuric-acid test. Under the microscope, oleomar- 
garine shows marked crystallization, pure butter is 
perfectly even, and butterine contains excess of oily 
matter. With sulphuric acid, butterine gives a ycl- 
lowish tint, which passes through a brownish amber 
to a final vandyke-brown color. Oleomargarine gives 
a yellow color, which gradually deepens toa red or 
erimson. With butter, sulphuric acid produces a 
whitish tinge at first, which soon changes to a salmon 
color, but never becomes crimson. If the butter has 
been colored with annatto, the color will be blu- 
ish green to black at first, but brick-red or salmon 
afterwards. With the polariscope and selenite plate, 
butterine gives a uniform plain tinge, red or green, 
while oleomargarine is distinguished by the colors 
produced by fat crystals. Dr. T. M. Chatard gave 
an account of a modified process for the estimation 
of alkalies in silicates, which is based upon Hem- 
pel’s method of decomposition with bismuth oxide. 
One part of the pulverized mineral, intimately mixed 
with two parts of bismuth oxide, is heated to redness 
over a Bunsen burner for about twenty minutes. 
The mass is then decomposed by strong hydrochloric 
acid; the excess of acid is evaporated off; the diluted 
solution is precipitated by ammonia and ammonia car- 
bonate, and filtered. In the filtrate are the alkalies 
and magnesia, to be separated by the usual method. 
The process is easy and rapid. —— Mr. E. Richards 
next gave some notes on the specific gravity of milk 
and whey. ‘The whey seems to be more constant in 
specific gravity than milk. A. E. Knorr and H. W. 
Wiley described the manufactureand use of very thin 
glass dishes for certain purposes in the analysis of 
organic products. The dishes are so thin and light 
that they may be pulverized, with their contents, pre- 
liminary to the combination analysis of the latter. 
Several of them were made before the society. 
Natural science association, Staten Island. 
April 12.—Mr. Charles Butler read a paper on 
experiments upon cross-breeding of moths. Last July 
he placed a recently hatched female of Callosamia 
Promethea out-doors in a box to secure some males 
of the same species, but caught six male C. angulifera 
within an hour of the time of the first exposure. 
The following night he caught five more with a new 
female, and the next night only one, and no C. Pro- 
methea. He noticed the fact that both of these spe- 
cies are not found about the vivarium at the same 
time. C. Promethea comes in the afternoon, when 
the sun is still up: C. angulifera comes after sunset. 
Mr. Bruice of Brockport says that a female Samia 
ceanothi, a California species hatched by him, at- 
tracted the males of S. Cecropia in great numbers. 
| 
Mr. Pilate of Dayton, O., states that he tied a female 
S. Cynthia out-doors over night, in order to obtain 
some eggs, and the next morning found her attached 
toa male S. Cecropia. Mr. Cook of Lansing, Mich., 
had a female S. Cecropia that attracted a score or 
more of 8. Columbia. 
Society of arts. Massachusetts institute of technology. 
April 10. — Mr. Thomas Pray, jun., spoke on 
the subject of the cotton-fibre and its structure, as 
shown by the microscope. A photograph was shown 
of a stalk carrying two hundred and twenty-five 
ripened bolls: and it was stated, that by the method 
lately practised, of developing this variety by carefully 
selecting the seeds of the best bolls, and planting them 
apart from others, and continuing this process during 
several years, it had been conclusively proved that 
it was perfectly possible to bring the yield of lowland 
cotton up to three bales per acre, with proper fertili- 
zation and favorable season; whereas, at present, a 
yield of one bale per acre is very large, the average 
being less than one bale to two acres. Inthe method 
of ginning at present practised, the seeds of all the 
different varieties of cotton ginned are indiscrimi- 
nately mixed; and the planter who brings his cotton 
to the gin, thongh receiving the same cotton back 
again, gets, for every bale ginned, a certain number 
of bushels of this miscellaneous mixture of different 
seeds, from which his next year’s crop is planted. 
No pains whatever have been taken to develop good 
varieties of cotton, or to increase the yield per acre 
by a process of selection, except in rare cases within 
a few years. A number of photo-micrographs of 
cotton-fibres were shown, exhibiting their peculiari- 
ties of structure. The fibreis a wide or flat cylinder, 
with athickening at the edges, and thin in the centre, 
twisted into a spiral. The coloring-matter is oily or 
resinous, and, in drying, is deposited on the edges of 
little pockets occurring along the fibre. The better 
the fibre, the more perfect its spirality, and the more 
regular in shape and in position are these oily deposits. 
Wrinkles are also formed in the fibre when drying, 
becoming most marked in the perfectly matured dry 
fibre, thus affording another test of good cotton. 
The lack of spirality prevents the fibre from being 
twisted with others in such a way as to become 
intimately engaged with them. An illustration was 
shown of the cotton after it had passed through the 
saw-gin, clearly showing that the fibres had been torn 
apart, the ends showing plainly the mutilation by 
the saw-teeth. The speaker referred to the faults 
of the present methods of ginning, and pointed out 
the directions for improvement. An illustration was 
also shown of cotton, after passing the railway head, 
which is supposed to make the fibres parallel; where- 
as such is by no means the case. The speaker urged 
the importance of examining cotton by the micro- 
scope, and dwelt upon the advantages which manu- 
facturing corporations would gain by selecting their 
stock in this way. 
