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Full text of "Humidity in cotton spinning : a paper"

HUMIDITY 



IN 



COTTON SPINNING. 




A PAPER BY 



B. A. DOBSON, C.E., M.I.M.E., 



CHEVALIER DE LA LEGION D'HONNEUR. # •♦ 





LIBRARY 



^t»^USf^ 




^ • 1895 • ^ 



'ayi' 



■.X:i''i'.>^ i^'fTv :^'i 




COPYRIGHTJ. [ALL RIGHTS RESERVED. 



HUMIDITY 



IN 



COTTON SPINNING. 

A PAPER BY 

B. A. DOBSON, C.E., M.I.M.E., 

CHEVALIER DE LA LEGION D'HONNEUR. 
(author of "the principles of carding cotton,'" 

" SOME difficulties IN COTTON SPINNING," &C., &C.) 

READ AT THE 

BOLTON TECHNICAL SCHOOL. 



before THE TECHNICAL INSTRUCTION COMMITTEES, MASTER COTTON SPINNERS, MILL 

MANAGERS TECHNICAL ASSOCIATION, AND MANAGERS AND OVERLOOKERS 

ASSOCIATION OF BOLTON AND DISTRICT, AND COMMUNICATED TO THE 

NEW ENGLAND COTTON MANUFACTURERS ASSOCIATION, 

BOSTON, U.S.A. 



7th DECEMBER, 1894. 



BOLTON : 
G. S. HEATON, PRINTER, VICTORIA WORKS, BOWKER'S ROW, 

1894. 



23336 



Op. Cetl , 

r^ IS77 



PEEFAGB 



What I intended originally to be a few Notes on 
the subject of Humidity in Cotton Spinning has, by 
force of circumstances, expanded into a fairly sized 
booklet. Again, whereas, at first, no illustrations were 
comtemplated, I have found it necessary, for the pur- 
pose of explanation, to include several. I trust the 
result may be of practical benefit to the trade con- 
cerned, if not directly by the information I have given, 
at least indirectly by the criticism it may induce. 

. B. A. DOBSON. 



Bolton, 

December, 1894. 



HUMIDITY IN 
COTTON SPINNING 




HE general interest taken in this subject, judging 
by the number of papers lately read and the 
discussions upon them, only points to the fact that it is 
a subject, the scientific study of which has been some- 
what neglected. 

We in this part of England, in Lancashire, have too 
long considered that we are specially favoured by nature 
in some very great degree, and that outside this county 
fine cotton spinning has been next to an impossibility. 
This raises the question of climatic suitability ; and I 
propose to consider, shortly, from a practical point of 
view, those conditions which concern the subject, and 
the means of modifying unfavourable circumstances, in 
order to produce better results in the processes of manu- 
facture. 

Some two years ago, I caused to be made an elaborate 
system of observations in mills spinning difi'erent numbers, 
with a view of ascertaining what degree of comparative 
similarity in atmospheric conditions could be found in 
mills spinning much the same numbers for the same 
market, in trade competition. I discovered, to my 
surprise, that this important question was very much 
neglected from, as I have just said, a scientific point 
of view. There are many mills where there are no 
instruments for ascertaining, exactly, the climatic con- 
ditions — in some other establishments, however, the use 
of them forms part of the duty of the staff and of the 



daily routine. I found, further, that where science had 
not been consulted the natural resource of the work- 
people exhibited itself in the most practical and simple 
way. Thus, in weather when a dry east wind and low 
temperature produced an atmosphere unfavourable for 
spinning, that friend of the cotton spinner, the "degging 
can," came into legitimate and successful operation. 

The climate most resembling that of Lancashire is 
the flat plain of Lower Flanders, known now as the 
Departement du Nord, in which is situated the wealthy, 
important, and thriving town of Lille. 

The cotton spinning industry in this district is 
almost as old as that of this country. And I may say, 
as regards fine spinning, it has been carried as far 
towards perfection as it is here ; and that so far as 
results are concerned, the people have little to learn 
from us. On the other hand, the fact of the mills 
being comparatively small, with a limited number of 
spindles to each establishment, causes an uneconomical 
result in cost of production which, in spite of duties, 
permits of competition from our own country. 

OLD COTTON MILLS IN LILLE. 

It may be said, broadly, that the mills constructed 
some seventy or more years ago were built exactly on the 
same plan as the mills erected in the city of Manchester 
and district at the same date, or previously, allowing 
for the peculiarity of construction obtaining in the two 
countries. 

Thus the buildings had thick walls and small win- 
dows, and the ceilings were lower. The entrance to 
each spinning room was from the staircase, well protected 
below from sudden incursions of cold winds; and the 



floors, and woodwork generally, were saturated with many 
years' accumulation of oil. This circumstance alone is of 
importance, inasmuch as the oil would form a sort of 
protection against sudden changes of temperature of the 
floor or walls or ceilings. Again, the small size of the 
rooms, and the little opportunity for the entrance of 
extraneous air, made the problem of maintaining an 
equable temperature one easier to solve. 

It is within my knowledge that a firm in this county 
of Lancashire, having a very ancient building constructed 
according to the foregoing particulars, and having a 
modern mill with increased floor space, window space, 
and height of ceiling, have found it impossible to spin the 
same numbers with equal results, the yarn from the old 
mill invariably being smoother. This will form the text 
upon which I am proceeding. 

EELATION OF HEAT TO FIBEE. 

It may be well to state at this point — although I 
presume most persons in the business of cotton spinning 
know it as well or better than I do myself — the reasons 
why cotton will spin better at one time than another. 
There are two causes for this, one of which hinges upon 
the peculiarity of the structure of the cotton fibre. If 
the cotton fibre be cold and dry it is what is termed 
''harsh ;" and a spinner who is accustomed to pull cotton 
can instinctively make allowance for the degree of dryness 
of that cotton he is testing. When the fibre is cold and 
dry the waxy envelope of the fibre is congealed ; and, 
consequently, there is some resistance of the fibre to the 
processes of manufacturing, known as "drawing" and 
"spinning." Although I have stated this very simply, I 
believe I have named all the facts as regards the relation 
of heat, ;per se, in its effect upon the fibre. 



Now if this were all, it would be enough if heated 
air were supplied in sufficient temperature to maintain 
the fibre in a supple condition. But here comes in 
another factor in the problem. If the fibre be hot and 
dry it is peculiarly susceptible to the influence of 
electricity. This is a phenomenon often most difficult 
to deal with. 

EFFECTS OF ELECTEICITY. 

From first to last, in a cotton spinning mill, free 
electricity interferes in each operation with the process 
of manufacture. Opener, scutcher, card, drawframe, 
flyframe, and mule or throstle— if the conditions are 
such that electricity has perfect hberty, the result must 
show inferiority of the product. I have seen mills of 
recent construction, especially fireproof mills, where 
every shaft, column, and beam in the fabric of the mill 
were charged with electricity to such a degree that cotton 
fibre stood out from the ironwork to the distance of at 
least three inches— radially to the centre of electric 
attraction. An infalhble and ready proof of the existence 
of the electricity is in carefully observing the ironwork of 
the machines. Of course, in all mills, there is a certain 
amount of loose fibre called "fly" floating in the air. 
If it is found on any of the ironwork standing straight up 
from the surface hke the bristles of a brush, there is no 
necessity for further argument— the presence of electricity 
is declared. Very often this comes from the slipping 
friction of the driving straps and is conveyed, say, from 
the driving shaft pulley to the pulley of the machine ; 
charging the body of metal with latent electricity, which, 
in its turn, affects every fibre in its passage. 

I have tried, occasionally, to extract the electricity 
from the machine, with very considerable success. Thus 



with a copper wire attached to any part of ironwork 
forming what is termed "earth," by placing the other 
end of the wire near the inside of the leading strap, the 
electricity was taken from the strap and prevented from 
going into the machine itself. On a revolving flat 
carding engine, which was so charged by electricity 
that the fly on the flats stood straight up from the wires. 
I have been able, by the movement of the wire, to make 
this fibre rise and fall at will. In combing machines, 
where it is desired to comb as much width of lap as 
may be practicable for the length of the roller, this 
action of electricity is very marked, and becomes of 
great importance. 

A very large and eminent spinning firm in America 
had a number of combers made to comb the same width 
of lap as they had seen successfully combed in a mill in 
this country ; but after a year's trial they found so much 
difficulty and so much waste made that they went to the 
extreme course of sending their manager to England 
to see, again, the machines which had served as a sample 
for the giviug of the order ; to ascertain whether they did 
work as satisfactorily as the firm had supposed. They 
found that the machines did so ; and the firm were 
forced to the conclusion that they would have to comb 
a lap one inch narrower than we can do in Lancashire, 
on account of the effect of the latent electricity upon 
the loose fibres of cotton. 

The action is to separate the fibres. Fibres under 
this influence cannot be brought together ; consequently, 
more room is required for the operation. I have, myself, 
seen not once, but several times, the cotton issuing from 
a drawframe roller refuse to pass down the funnel to the 
coiler, and float in the air like a snake right over the 
calender rollers on to the floor. 



6 

What is true of the card, comber, and drawframe, 
is also true of the flyframes and spinning machines. 
But in the spinning machines the presence of electricity 
is shown by accumulation of fly on the working parts — 
the rough, furry, character of the thread made, and 
its brittleness and liability to snap. As showing the 
extraordinary effects that can be produced by this, I know 
of a mill which, when starting its new machinery, had 
several breakdowns of the openers and scutchers ; but, 
more particularly scutchers, after stopping the machine 
and restarting. A little observation showed that in each 
case a huge parcel of cotton of considerable density had 
been carried to the metallic cages, and, by over pressure, 
owing to the great thickness, had caused breakages of the 
wheels. A little examination showed that, after running 
some time, the whole of the interior of the beaters, from 
the centre shaft to the blade of the beater, contained a 
dense block of cotton, which filled in the space as 
symetrically as if it had been made purposely in wood. 
After a certain time, when the machine had been 
stopped long enough to allow the electricity to be dis- 
engaged, these pieces fell as the machine restarted and 
were thrown by centrifugal force into the cages. 

I examined these extraordinary blocks of cotton and 
found that the fibres were ranged parallel end to end in 
line from the centre of the beater shaft to the inside 
surface of the beater blade. In this case, the objection- 
able phenomenon disappeared as soon as the room had 
been heated, and the straps driving the machine had been 
thoroughly well moistened with composition. The fact 
was the machines were at first thoroughly insulated from 
the floor ; the driving strap slipping on the line shaft 
pulley was acting as a sort of electric machine and 



charging, by means of the strap, the opening or scutching 
machine driven. 

In America, this has been considered of such 
importance that in many mills there are special arrange- 
ments for preventing conduction of electricity from the 
driving straps to the machines. 

Mr. Buchanan saj-s in the Phil. Mag., U.S., Yol. I., 
page 581, that in a "factory at Glasgow the accumulation 
of electricity in one room in particular, in which was a 
large cast iron lathe, shears, and other machinery driven 
with great velocity by belts was so great that it was 
necessary, in order to protect the workmen from 
unpleasant shocks, to connect the machinery with 
copper wire with the iron columns of the buildings, and 
that when a break in the wire was made at a quarter of 
an inch the succession of sparks was very rapid. The 
electricity was positive." 

Thus in the case of the scutchers I have named the 
phenomenon ceased when the slipping of the strap was 
prevented by the composition which, at the same time, 
acted as a non-conductor, preventing the surface of the 
leather from touching the surface of the iron drum. 

In connection with this subject of electricity and its 
practical effect upon spinning, I would refer to a pamphlet 
by Mr. Harry S. Chase, read at the Massachusetts Insti- 
tute of Technology, in 1883, in which the phenomenon 
occasioned by electricity in spinning white cotton, dyed 
cotton, and natural and dyed wools, is very fully dealt 
with ; and in which the author describes different 
methods by which electricity can be generated in a 
spinning mill and communicated to the material under 
operation ; as, also, the best method of preventing or 
removing the electricity. It would seem from the result 



8 

of Mr. Chase's investigaMons that the principal cause is 
the friction occasioned by the sKp and pressure of the 
strap on the driving pulley, in which, as in all electrical 
phenomena, the surface of the strap will produce one 
electricity and the pulley another. In every case tested, 
the electricity developed was negative in the belt and 
positive in the pulley. Above and beyond the difficulty 
occasioned by this occurrence, there is a greater one in 
that the stock of material may be charged with electricity 
generated elsewhere, and communicated by beams, pillars, 
gas pipes, or bolts. Cases have been known where the 
cotton in the mixing room was severely charged from the 
bolt heads of the hangers driving the machinery pulley. 
It may be said, en passant, that material, either cotton or 
wool, charged with electricity is exceedingly difficult to 
discharge ; and only time and a kindly atmosphere can 
effectually perform this. The author also mentions the 
effect of steam being allowed to flow into rooms, 
principally weaving sheds, for humidifying purposes, in 
order that "electricity may be killed ;" and where it was 
found that the very opposite effect was produced, from 
the fact that steam was developing the same quahty of 
electricity as that existing in the room. The writer 
completes his paper by discussing the question of moisture 
in the air and the extent of steam admitted, further 
pointing out that a too great proportion of moisture would 
have an injurious effect upon the work, as the springs and 
elasticity of the fibre is weakened. He then makes some 
general remarks upon the observations of the hygrometer, 
and draws a conclusion with which I must strongly 
disagree ; one in wln'ch he states that the humidity for 
good working is less than expected, and he places the 
limitation between bad and good work at from 30 to 40 
per cent, of saturation. This I think will, further on, be 



9 

seen to be quite outside the mark ; and Mr. Cliase winds 
up with an assertion I reproduce literally: "A careful 
consideration of these statements will satisfactorily prove, 
I think, that the whole question of escaping from electri- 
cal trouble will be found in the matter of relative 
humidity. If there is sufficient moisture in the 
atmosphere, there is no trouble ; if there is not sufficient 
moisture, electricity always appears. The question is 
resolved into deciding on the best and most satisfactory 
method of getting the moisture into the mills and this 
brings in, as all improvements ultimately do, the 
consideration of the relative cost of the annoyances and 

ft/ 

the cure." 

HYGKOMETEICAL CONDITIONS OF THE 
ATMOSPHERE. 

Now the author might have gone even further than 
he has done, and pointed out the impossibility of produc- 
ing good yarns in either cotton or wool, if the hygro- 
metrical conditions of the atmosphere were unfavour- 
able ; the reason being, as I have stated before, that the 
effect of the existence of the free or latent electricity is to 
produce mutual repulsion in the fibres being dealt with ; 
and therefore in the processes of spinning and twisting 
the end of the fibre not immediately under control has a 
tendency to radiate from the centre of the body of fibres 
in action, and to produce rough, or what is familiarly 
known as ''oozy" yarn. I may say that the only 
effective method of avoiding the inconveniences previously 
alluded to is by moistening the air to such an extent that 
it will prove a sufficiently good conductor to disengage 
the electricity existing in the fibres. 

In countries where there is a very wide range of 
temperature and where the climate at certain seasons is 



10 

excessively dry, these differences are more serious than in 
countries where the contrary obtains ; although even in 
this climate of Lancashire the difference between a west 
wind and an east wind often makes a margin of 7 to 8^- 
per cent, in the production of a weaving shed. 

Boston is the chief town of Massachusetts and is, to a 
certain extent, a centre of manufacturing, and may almost 
be termed the American Manchester. The mills are not 
immediately in the town. They are at short distances 
round and are in practically much the same climate as 
the town of Boston itself. What difference there is, is 
perhaps rather against the manufacturing districts, as 
most of them are inland from Boston, and, consequently, 
there is slightly less humidity than in the neighbourhood 
of the coast line, where the vicinity of the ocean tends to 
make the climate equable. 

COMPAKISONS OF DISTRICTS. 

In making a comparison between one district and 
another, as regards its capabilities for manufacture there 
are several points wdiich must be carefully weighed in all 
cases ; the first being tbe question of mean temperature, 
the second the extreme range of temperature, and the 
third the natural percentage of humidity under the 
varying temperatures. I append a table of statistics with 
regard to the foregoing conditions and will endeavour to 
deduce the values, for the purpose of manufacturing — 
say cotton spinning, in each case. I have taken twelve 
parts of the world— the 10th, 11th and 12th being, res- 
pectively, Boston (Mass.), Bolton, Lancashire, and the 
district near Lille. I will proceed to show why, and to 
what degree, each is favoured by its climatic peculiarities 
for this particular industry. I have given in each case 



11 

the maximum and minimum temperature and the mean 
maximum and minimum of humidity, and, also, the cal- 
culated annual mean. The latter is of little value as a 
factor in the problem, as, of course, extremes of condi- 
tions of humidity would not affect the calculated mean ; 
although one extreme, or the other, or both, might 
be very prejudicial to the working of the fibre. And I 
may state, as a principle, that the less the range of tem- 
perature, and the more regular the degree of humidity, 
the better the conditions. Thus, for instance, take the 
contrast between Boston and Bolton. I find the highest 
monthly mean humidity in Boston to be 85 per cent., 
against Bolton 93-1 per cent. ; the lowest monthly mean 
66 per cent., against our 69 per cent. Moreover, 
comparing the annual mean humidity, Boston 74*5 per 
cent., and Bolton 81 '9 per cent., the contrast shows 
an immense advantage for cotton spinning here. Again, 
take the range of temperature — in Bolton it is 62*8 deg., 
whilst in Boston it is 92 deg. 

When the temperature in Boston is minus 1 degree, 
the amount of vapour in suspension would be practically 
nil, or about half a grain per cubic foot ; consequently, 
when the air is heated sufficiently to allow of spinning 
operations, it would be absolutely necessary, even for 
considerations of health alone, to impart an artificial 
humidity. The conditions of the district near Lille will 
be seen ; they resemble closely those of Bolton. 

On the following page will be found the tabulated 
statement referred to, with criticisms on the adaptability 
of the various climates for spinning. 



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DIAGRAM OF SATURATION 

BY B.A.DOBSON 


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14 



INFLUENCE OF VAPOUR. 

That those who have not had au opportunity of study- 
ing the question of the principles involved in evaporation 
and in suspended vapour may do so, I append a table 
diagram on page 13 from which may be seen, at a glance, 
the weight of vapour per cubic foot, or per cubic metre, 
which constitutes what is known as saturation ; satura- 
tion, of course, meaning that each particle of air is 
supporting as much weight of fluid in its minute globular 
form as it is capable of doing. This is known as the 
elastic force of aqueous vapour. The table is read from 
the perpendicular column on the left to find the number 
of grains per cubic foot, and along the upper column to 
find the temperature on the Fahrenheit scale. On the 
right hand are the number of gramms per cubic metre, and 
on the bottom the scale of temperature on the centigrade 
scale. Thus, by reading up from the bottom and from the 
left, the weight of aqueous vapour required to saturate a 
cubic foot at any temperature in the scale can be readily 
seen, and the same by reading from the right hand side 
and from the bottom for the metric system. It will be 
seen that, as the temperature rises, the air is capable of 
containing more and more moisture. Thus, at 212 
degrees Fahr., the air would be developing steam, and 
that at 40 degrees below zero, Fahr., the air is not capable 
of supporting vapour. 

This, of course, accounts for the bright crisp air in 
excessively cold weather, and for the muggy damp air 
occasionally met with in the dog days. It accounts, like- 
wise, for the phenomenon met with in the cold coun- 
tries, such as Canada or Russia, where, on a bright sun- 
light day, with a blue sky, finely powdered snow falls in 
quantity ; the fact being that a stratum of air which, by 



15 

its greater temperature has absorbed moisture, elsewhere, 
is suddenly congealed and obliged to part with that 
portion of vapour over and above its proper quantity 
for its temperature. Further, it is responsible' for the 
heavy dew in hot weather, where, when the air has been 
heated all day, and the moisture of the earth and the 
surface of adjacent water has been evaporated by the 
heat of the sun, and taken into suspension by the heated 
air, at sundown, the difference of temperature, owing to 
terrestrial radiation, forces the air to part with its excess 
of moisture. Thus, as I have practically proved, it is 
possible in the tropics, to become wet through in a two 
miles' walk after 9 o'clock in the evening, the moisture 
formed on the clothing being visible and perceptible to 
touch. 

In the proceedings of the Koyal Meteorological 
Society of January, 1893, under the heading of " Corres- 
pondence and Notes, " there is a statement referred to by 
Mr. F. E. Saunders in the "Bulletin of the New Eng- 
land Weather Service for September, 1892," in which 
he states : — 

"It is a well-known fact that the temperature has 
quite an important bearing upon cotton fibres during 
the manipulation from the bale to the cloth -room. 
This must be evident to the most casual observer when 
we consider the fact that cotton is grown in a warm 
climate, surrounded by a mean temperature of 70 
deg. and then transmitted to a climate that is subject 
to sudden atmospheric changes, many of them being of 
low temperature and with an atmosphere divested of 
moisture. 

" Cotton fibres are very susceptible to any atmos- 
pheric change ; that is to say, they will take on or throw 



10 

of! dampness very readily, consequently any material 
change of temperature and humidity will affect the 
successful working of the fibre. In order for cotton 
to work well in the first processes of manipulation, the 
dry bulb thermometer of the common psycbrometer 
should stand at 78 deg., and the wet bulb at 66 deg., 
which would make the dew point 58 deg., and the relative 
humidity 52 per cent. This would give 5'371 grains of 
water vapour per cubic foot of air. Cotton fibres, with 
this condition of atmosphere, will very readily assimilate 
and draw even. During very many of the atmospheric 
changes that are constantly taking place it is found quite 
impossible to bold the cotton fibres well in hand. This is 
more noticeable when dry atmosphere prevails with a dry 
west-north-west wind blowing for twenty-four or thirty- 
six hours. It is frequently the case, where these changes 
take place, that the amount of water vapour in a cubic 
foot of air will drop as low as 4*29 grains. When these 
conditions occur the electrical currents of air seriously 
interfere with the workings of cotton fibres. Electricity 
causes the fibres to separate, and much more waste is 
made. Very many of the cotton mills in New England 
are not supplied with moistening apparatus.*" 

HUMIDITY AND TEMPERATUEE. 

It will be seen from the foregoing, that tbe question 
of humidity is intimately allied with that of temperature; 
and in manufactories it is first necessary to fix the 
temperature at which the workroom shall be kept and 
then to make such arrangements that this air may be 
supplied with the amount of moisture sufficient to make 
the air soft enough for the comfort of the workpeople and 

* The use of hygrometers to indicate the eonditiuii of uliuosphere in Kpinuing mills was rendered 
couipulsoiy iu Eiiglaud by the Cottou Cloth I'aetoiits Act, lt*iU. 



17 



the conditioning of the fibre, and to render the atmos- 
phere a sufficiently good conductor to subtract the 
extraneous and superfluous electricity. The following 
table gives the maximum amount of humidity allowed 
by the Act of Parliament referred to. It will be noticed 
that the vapour allowed is considerably in excess of any 
of the undermentioned observations : — 

COTTON CLOTH FACTORIES ACT, 1889. 



Maximum limits of Humidity of the Atmosphere at given Temperatuees. 







Grains of 


Percentage 

of 

Humidity 

Saturation 

= 100. 

80 






Grains of 


Percentage 

of 

Humidity 

Saturation 

= 100. 


Dry Bulb 


Wet Bulb 


Moisture 


Dry Bulb 


Wet Bulb 


Moisture 


Beadings. 


Readings. 


per cubic 
foot of Air. 


Eeadiugs. 


Readings. 


per cubic 
foot of Air. 


350 


330 


1-9 


680 


66" 


6-6 


88 


36 


34 


20 


82 


69 


67 


6-9 


88 


37 


35 


2-1 


83 


70 


68 


7-1 


88 


38 


36 


2-2 


83 


71 


68-5 


7-1 


85-5 


39 


37 


2-3 


8i 


72 


69 


7-1 


84 


40 


38 


2-4 


84 


73 


70 


7.4 


84 


41 


39 


2-5 


84 


74 


70-5 


7-4 


81-5 


42 


40 


2-6 


85 


75 


71-5 


7-65 


81-5 


43 


41 


2-7 


84 


76 


72 


7-7 


79 


44 


42 


2-8 


84 


77 


73 


8-0 


79 


45 


43 


2-9 


85 


78 


73-5 


8-0 


77 


46 


44 


3-1 


86 


79 


74-5 


8-25 


77-5 


47 


45 


3-2 


86 


80 


75-5 


8-55 


77-5 


48 


46 


3-3 


86 


81 


76 


8-6 


76 


49 


47 


3-4 


86 


82 


76-5 


8-65 


74 


50 


48 


3-5 


86 


83 


77-5 


8-85 


74 


51 


49 


3-6 


86 


84 


78 


8-9 


72 


52 


50 


3-8 


86 


85 


79 


9-2 


72 


53 


51 


3-9 


86 


86 


80 


9-5 


72 


54 


52 


41 


86 


87 


80-5 


9-55 


71 


55 


53 


4-2 


87 


88 


81-5 


9-9 


71 


56 


54 


4-4 


87 


89 


82-5 


10-25 


71 


57 


55 


4-5 


87 


90 


83 


10-3 


69 


58 


56 


4.7 


87 


91 


83-5 


10-35 


68 


59 


57 


4-9 


88 


92 


84-5 


10-7 


68 


60 


58 


5-1 


88 


93 


85-5 


11-0 


68 


61 


59 


5-2 


88 


94 


86 


11-1 


66 


62 


60 


5-4 


88 


95 


87 


11-5 


66 


63 


61 


5-6 


88 


96 


88 


11-8 


66 


64 


62 


5-8 


88 


97 


88-5 


11-9 


65-5 


65 


63 


6-0 


88 


98 


89 


120 


64 


66 


64 


6-2 


88 


99 


90 


12-3 


64 


67 


65 


6-4 


88 


100 


91 


12-7 


64 



It would be well to here show what inquiries arid 
investigations I have made with a view of ascertaining 



18 

the exact working conditions obtaining in the district of 
Bolton, where our chmate is supposed to be specially 
favourable for the spinning of super-extra quality of yarn. 
And I may say, in passing, it is a fact that no district 
has spun, so far, the special numbers and qualities of 
Bolton yarns to as good, or certainly not to better, 
advantage than is done here. 

Knowing, as I did, personally, the conditions ex- 
isting in a large number of manufactories, I could tell 
where and how to find the information that specially 
interested me. Therefore it was a more simple matter 
than would at first appear to find the typical examples 
and make the necessary comparisons. My examples 
have covered fifteen different mills, of which two were 
engaged in spinniug wool. The numbers spun in these 
mills ranged from 40's to 160's. The mill spinning 160's 
had been arranged for much finer numbers, but, owing 
to the vagaries of the market, had spun considerably 
coarser numbers. Most of the mills were mule spinning; 
but one was a ring spinning mill, and one of the woollen 
mills was cap frame and the other mule spinning. I am 
glad to render tribute to the alacrity with which my 
request for permission to make these investigations was 
accorded in all cases. The only stipulation was that I 
would keep to myself the names of the firms concerned. 
This, I need hardly say, T have strictly complied with. 

ADVANTAGES OF HYGROMETERS. 

As will be seen from the foot- note to Mr. Saunders' 
remarks, the use of hygrometrical thermometers under the 
Cotton Cloth Factories Act, 1889, is compulsory. But 
the provisions do not extend to spinning mills. It is a 
great misfortune that it should not be wholly compulsory, 
because it would result in a better understanding of the 



19 

most favourable conditions for manufacture. In every 
case where I have examined the instruments I found the 
same radical defect. That is to say, the wet bulb and its 
well are so near the dry bulb as to affect the truth of the 
reductions of observation from 8 to 13 per cent, in the 
amounts calculated as percentage of humidity. Thus, in 
most cases, the thermometers were only 2^ inches apart, 
and one I noticed in particular only li inches. Now the 
thermometers should not be less than 4 inches apart, and 
the well of the wet bulb should be at least 5 inches from the 
dry bulb. Even then, if observations are carefully noted, 
it will be found there is a difference of from 1 to li per 
cent, in apparent humidity between an observation in 
which the dry bulb is frequently wiped with a dry cloth 
and that in which it is left to acquire the moisture from 
the wet bnlb, even at the distance of 4 inches. Thus in 
twenty-one readings under average circumstances, after 
allowing for corrections for what are known as " certified 
index errors," the standard instrument showed 83-1 deg., 
as against the mill instrument 777, and the standard 
instrument 95-2 against the other 89 deg. By carefully 
working out the figures, say of the first observation, 
it will prove, after the proper correction, a relative 
humidity to saturation, of 37 per cent, by the standard 
instrument and 55 per cent by the mill instrument. This 
will show how the mill people are deceived when they 
imagine that they are approaching the limit of humidity 
allowed by Act of Parliament, whereas, as a matter of 
fact, they are scarcely within measurable distance. 

Those who have had to make the calculations to 
arrive at the percentage of humidity when worked out by 
what are known as Glaisher's Tables, will know there is 
a considerable amount of calculation, and if the observa- 



20 




21 

tions are repeated and numerous, it is no small work to do 
this correctly. 

Now as the principle involved in the differential 
value of the readings of the two thermometers follows an 
exact mathematical rule, it must be obvious there can be 
a mechanical method of reading the result without the 
calculations by means of curves or diagramatic interpreta- 
tion. This principle has been most ingeniously worked 
out by an instrument-maker named Lowe in the town of 
Bridgeport, Connecticut, U.S., A. With this instrument 
it is only necessary to read the temperature of the dry 
bulb (64°), then place the lower edge of the upper steel 
finger, seen to the left of the instrument, opposite the 
same temperature on the graded scale. This is done 
by sliding the milled head up or down as required. 
Then read the temperature of the wet bulb (58-7°), 
and turn the same milled head until the upper edge 
of the lower steel finger is level with that temperature. 
In doing this you move levers which bring the point 
of the indicator to that part of the chart where the 
relative humidity (72%) can be read off— each of the 
thick vertical curves representing 10%, and the inter- 
mediate ones 2%. Other curves give the temperature 
of dew-point, and the weight of vapour per cubic foot 
of air. Upon testing, by exposing it alongside the 
two standard hygrometers, I found it took the large 
spherical bulbs of the thermometers four times as long 
to adapt themselves to the temperature of the mill as 
the long oval-shaped bulbs made by Casella of London; 
and the scale, being graded on the brass mountings 
instead of the stems of thermometers, gave reductions 
showing 7% more humidity than existed. This differ- 
ence may arise either from the thermometers having 
slipped in the mount, or incorrectness of scale. 



22 




23 

Another very ingenious instrument, "The Hygro- 
phant," is one made by Huddleston of Boston, U.S., A. 
This is even easier to understand than the preceding- 
one, but confines itself to the finding of percentage of 
humidity. Indeed it is so simple that it might be 
called " Hygrometry made easy." First ascertain the 
number of degrees of difference between the temperatures 
of the wet and dry bulbs, then turn the vertical 
revolving drum placed between the thermometers until 
the figure in larger type at the head of the column on 
the drum is the same as the difference of degrees; 
then, reading on the central scale the degree of 
temperature on the wet bulb thermometer opposite this 
figure on the revolving drum, is found the degree of 
humidity in the atmosphere. This instrument, as 
received from the maker, was tested at a temperature 
of 88", when four observations gave a mean excess of 
humidity of 107o- The original heavy connecting 
strands from the well to the bulb were then removed, 
as they locally increased the humidity of the air near 
the bulbs, and a connection composed of eight strands 
of soft darning cotton was substituted, with the result 
that the next four exposures showed only 4% of error. 
These thermometers, too, were not graded on the 
stems, nor had any of them been verified. I believe 
these discrepancies would not occur if the instruments 
were mounted with correctly made and verified 
thermometers. Either pattern, on account of there 
being no necessity for the use of tables and calculations 
for reduction, would be very serviceable for mill use, 
if constructed correctly as regards grading and after 
having been tested. 

I make this difference still more distinct by 
appending a table of test experiments made by a 



24 



competent observer under the Kew Observatory rules 
between the standard London instruments — having been 
duly tested — and the thermometers of Huddleston's 
instrument. The difference is remarkable and, as can 
be seen, is greatest at the highest temperatures. 

COMPARATIVE READINGS AND REDUCTIONS OF CASELLA'S 
HYGROMETER AND HUDDLESTON'S HYGROPHANT. 



AUG. 27/94. 


CASELLA'S. 


HUDDLESTON'S 


Time. 


Dry Bulb " 


Wet Bulb ° 


Humidity "/o | 


Dry " 


Wet ° 


Humidity °/o 


11-45 

12-45 

1-45 

2-45 


60-7 
60-7 
60-8 
610 


57-2 
57-4 
57-2 
57-5 


Exposed 

79-7 
80-9 
79-2 
79-5 


in the Shade. 

60-7 
60-7 
60-8 
60-9 


57-9 

67-8 
57-8 
57-9 


83-9 
83-3 
82-4 
82-9 


3-30 
3-45 
4-0 


87-7 
88-3 
88-7 


75-7 
75-8 
76-1 


Exposed in 

52-0 
50-5 

48-2 


Spinning 

82-2 
84-3 
85-8 


Boom. 

74-3 
75-0 
75-9 


64-6 
59-1 
58-3 


5-0 
5-45 
6-45 
7-45 


58-9 
58-7 
58-5 
58-4 


57-3 
57-0 
56-9 
56-8 


Exposed in 

89-7 
88-8 
89-4 
89-4 


a Cellar. 

61-2 

' 59-3 

58-9 

58-7 


58-4 
57-5 
57-2 
57-0 


83-4 
89-2 
88-8 
88-8 



In every case the instrument, to be reliable, must 
comply with certain standard requisites : the distance 
apart of the thermometers, the position of the well of 
water, size of the aperture of the neck of the well bottle, 
and the thickness of the strands conveying the moisture 
from the well to the wet bulb. All should be in conson- 
ance with the experience of those who have made a 
careful study of this subject. In all cases of my 
observation, two standard instruments were employed, 
furnished with the same water, attached on opposite sides 
of the same pillar or column of the mill ; and the 
reductions were calculated from Professor Glaisher's 
Hygrometrical Tables, 7th Edition, the tenths of a degree 
in either bulb being worked out by interpolation with 
the nearest factors.* 

* Since the above was written Messrs. Casartelli of Manchester have produced a Mill HyHrometer 
which conforms to the rcquircmcnta, theoretical and practical, lierein enunciated, and which is free from 
tlic ordinary defects of this class of inbtrumeut. It has been tested against the standard Kew instrument 
and found unimpeachable in accuracy. 



25 



HYGEOMETKICAL OBSERVATIONS IN COTTON SPINNING. 



EEDUCED AS PER PROF. GLAISHER'S " HYGROMETRICAL TABLES," 7th EDITION. 









Hygrometer. 


Dew. 


Elastic 
force 


Weight of 

Vapour 

per Cubic 

Foot. 


Maximum 
Weight 


Weight of 

Vapour 

if 

Saturated 


Humidity 


Humidity 

of the 

Outside 

Air. 


Mill. 


Room. 


Counts. 


Dry 
Bulb. 


Wet 
Bulb. 


Point. 


of 

Aqueous 

Vap. 


of 
Legal 
Limit. 


of 
Room. 


"A" 
























[A] 


























Cards 




79.40 


64-60 


54-50 


0-425" 


4-54 grs. 


8-17 grs. 


10-76 grs. 


42 0/0 


940/0 




No. 2 Sping. 


68—88 W 


83-1 


65-6 


54-0 


•417 


4-48 


8-83 


12-13 


37 


/ u 




„ 3 do. 


68—88 W 


860 


706 


600 


-618 


5-58 


9-50 


13-20 


42 






„ 4 do. 


68—78 W 


85-1 


69-8 


69-8 


•517 


5-43 


9^18 


12-90 


42 






,. 5 do. 


68 W 


89-6 


72-6 


62-0 


-563 


5-82 


10-07 


14-64 


40 




[B] 


























Cards 




83-5 


67-0 


66-0 


•449 


4-75 


8-70 


11-70 


39 


94 




No. 2 Sping. 


94—120 W 


87-2 


71-8 


61-1 


•539 


5-68 


9-49 


13-69 


42 






„ 4 do. 


112—128 W 


91-5 


75-6 


65-8 


-633 


6-37 


10-20 


14-74 


43 




[C] 


„ 7 do. 


115—135 W 


85-7 


71-8 


62-7 


•572 


6-00 


8-99 


13-08 


48 


„ 


Cards 




77-0 


620 


51-5 


-381 


4 10 


8-00 


10-00 


41 


94 




No. 2 Sping. 


90 W 


93-3 


75-0 


63-8 


•593 


•6.19 


10^91 


16-37 


37 






„ 3 do. 


90 T 


95-2 


76-7 


65-6 


•632 


6-56 


11^44 


17-06 


38 






„ 4 do. 


80—90 T 


91-1 


75-3 


65-6 


•6-26 


6 58 


1032 


1534 


42-5 


" 




„ 5 do. 


90 T 


91-9 


76-2 


66-6 


-651 


683 


1008 


15-70 


43 


" 




Combers 




77-0 


61-9 


51-3 


-379 


4-08 


8-00 


10-00 


41 


" 


[D] 


























Cards 




82-9 


66-8 


55-8 


•450 


477 


8-41 


11-25 


40 


94 




Frames 




87-7 


68-5 


56-2 


-453 


4-78 


9-34 


13-88 


35 






No. 3 Spirg. 


90 W 


93-0 


74-8 


63-7 


-590 


6-14 


1100 


16-20 


37-5 






„ 4 do. 


90—89 T 


946 


77-0 


66-4 


-648 


6-74 


10-92 


17-00 


42 






„ 5 do. 


70—100 T 


93-5 


77-9 


68-5 


-695 


7-30 


10-85 


16-45 


44 


" 




„ 6 do. 


100—120 T 


88-7 


74-8 


660 


•638 


6-75 


9-76 


13-59 


47 


>i 


"B" 

[A] 
























Cards 




71-3 


58-6 


48-9 


•348 


3-79 


7-04 


8-36 


45 


80 




No. 1 Sping. 


120—160 W 


93-5 


73-9 


62-0 


-556 


5^81 


10^85 


16-45 


35 






„ 2 do. 


110—140 W 


93-7 


73-6 


61-4 


•545 


5^67 


10^79 


15-71 


34 


" 




„ 3 do. 


110—140 W 


96-1 


74-3 


61-4 


•545 


5-68 


11-76 


17-75 


31-5 






„ 4 do. 


85—120 W 


85-1 


69-8 


59-8 


•517 


5.23 


918 


12-64 


42 


" 


[B] 


























Cards 




73-7 


62-2 


53-8 


'416 


4-49 


7^28 


8-47 


49-5 


80 




No. 1 Sping. 


110 W 


86-8 


68-9 


.57-4 


•472 


4-99 


9^26 


13-52 


36 






;, 2 do. 


110—120 W 


90-6 


73-5 


62-9 


•511 


5-99 


1003 


1510 


40 






„ 3 do. 


100—120 W 


89-1 


72-5 


62-1 


•555 


5^84 


1022 


14-44 


40 


" 


[C] 


„ 4 do. 


120 W 


87-0 


70-0 


59-1 


•602 


5-30 


9^55 


13-60 


39 


i> 


Cards 




87-0 


69-3 


67-9 


-482 


5-90 


9-55 


13-60 


37-6 


80 




Frames 




88-3 


69-0 


56 8 


•461 


493 


9-81 


14-18 


34-5 






Combers 




70-5 


57-5 


47-6 


•330 


3-60 


7-08 


7-75 


46 


" 




No. 1 Sping. 


50 T— 78 W 


98-6 


77-4 


65-1 


-622 


6-40 


11-76 


17-22 


35 






„ 2 do. 


100 W 


96-7 


77-5 


66-3 


•643 


6-63 


11.59 


17-95 


37 






„ 3 do. 


60—80 W 


96-3 


77-5 


66-1 


-639 


6-57 


11-71 


18 13 


37-5 


" 




„ 4 do. 


60-80 W 


90-6 


72-9 


61-9 


•552 


5-81 


10-12 


15-10 


38-5 


" 



26 



HYGROMETRICAL OBSERVATIONS,— Co?)«Miuerf. 





Room. 


Counts. 


Hygrometer. 


Dew 
Point 


Elastic 

force 

of 

Aqueous 
Vap. 


Weight of 

Vapour 

per Cubic 

Foot. 


Maximum 
Weight 

of 
Legal 
Limit. 


Weight of 

Vapour 

if 

Saturated. 


Humidity 

of 

Room. 


Humidity 
of the 


Mill. 


Dry 
Bulb. 


Wet 
Bulb. 


Outside 
Air. 


[A] 
























Cards 




79-20 


63-7" 


,5330 


0-404" 


4-32gis 


8-21grs 


10 68grs 


41 "/o 


870/0 




No. 1 Sping. 


40—60 T 


92-5 


72-2 


59-8 


-513 


5-33 


10-55 


15-95 


33-5 


)) 




„ 2 do. 


.50—60 T 


93-6 


72-9 


60-3 


•525 


5-41 


10-82 


15-78 


32-5 


)> 


[B] 


„ 3 do. 


60—70 T 


91-6 


72-6 


60-9 


•533 


5-66 


10-17 


15-58 


36 


>i 


Cards 




80-6 


64-1 


52-9 


•401 


4-27 


8-40 


11-18 


38 


87 




No. 1 Spiug. 


60 T 


90-8 


70-8 


58-4 


•487 


5-16 


10-06 


15-20 


34 


,, 




„ 2 do. 


60 T 


91-3 


721 


60-2 


-5'20 


5-.50 


10-26 


15-42 


35-5 


)> 


[C] 


„ 3 do. 


60 T 


80-7 


67-1 


57-6 


-479 


5-16 


8-41 


11-21 


46 


" 


Cards 




70-70 


56-7 


46-2 


•312 


3-.37 


6-98 


8-21 


41 


87 




No. 1 Sping. 


40-60 T 


85-0 


61-8 


46-9 


•322 


3-40 


9-20 


13-20 


27 


,, 




„ 2 do. 


40—60 T 


62-9 


50-7 


40-3 


•229 


2-75 


5-22 


5-88 


43-5 


„ 




Winding 




58-7 


50-9 


49-4 


•288 


3-21 


4-58 


5-54 


58 


'• 


"D" 
























[A] 


Cards 




76-4 


620 


51-9 


•387 


416 


7.62 


9-82 


42 


87 




No. 1 Sping. 


62 T 


96-4 


75-1 


62-6 


■567 


5 91 


11-64 


17-92 


33 


,, 




„ i do. 


62 T 


102-4 


79-6 


64-6 


•609 


6-12 


13-40 


19-62 


31 


,1 




,, 3 do. 


52 W 


99 6 


78-6 


66-6 


-634 


6-72 


12 16 


19 60 


34 


1, 




„ 4 do. 


52 W 


89-3 


73-8 


64-1 


-595 


6-29 


10-16 


14-.52 


42 


J, 


[B] 


Cards 




83-70 


66-7 


55-4 


•438 


4-67 


8 71 


12-28 


38 


87 




No. 1 Sping. 


60 T & W 


920 


71-8 


59-4 


•505 


5-24 


10-70 


15-70 


335 


n 




„ 2 do. 


70 T & W 


99-0 


75 


61-3 


•550 


5-60 


12-30 


19-30 


30 


«> 




,, 3 do. 


62 T & W 


95-6 


72-7 


59-1 


•502 


5 15 


11-32 


17-50 


30 


>> 


"E" 
























[A] 


Cards 




85-7 


67-8 


56- 1 


•452 


4-77 


9-06 


13-08 


36 


94 




Frames 




83-9 


66-9 


55-6 


•443 


4-69 


8 88 


12-38 


38 


,, 




Combers 




77 5 


63-6 


53 9 


•425 


4-42 


8-10 


1014 


44-8 


,, 




No. 1 Sping. 


32 T 


94-8 


74-4 


62-1 


-560 


5-78 


11-34 


17-10 


34-2 


,, 




„ 2 do. 


60 T 


95-7 


75 6 


64-0 


-597 


6-11 


11-68 


17^49 


35-2 


>> 




„ 3 do. 


64 T 


94-1 


73-4 


60-9 


-535 


5-51 


11-14 


16-75 


33-7 






„ 4 do. 


50 T 


87-6 


69-6 


58-1 


-485 


513 


9-67 


13-85 


37-0 


•' 


"F" 

[A] 
























Cards 




75-2 


63-3 


,54-8 


•429 


4-79 


7 69 


9-46 


49 


95 




Frames 




79-8 


65-3 


55 4 


•439 


5-41 


8-41 


10-12 


42-5 


,, 




Combers 




81-8 


67-1 


57-2 


•469 


6-30 


8-76 


11-62 


42-7 


,, 




No. 2 Sping. 


90 


85-8 


71-8 


62-7 


-.570 


714 


9-36 


1312 


46-8 


)> 




,, 3 do. 


70 


85-6 


72-3 


63-6 


•589 


6 84 


9 32 


13-04 


48-1 


„ 




„ 4 do. 


65 


86-8 


73-4 


64-8 


•613 


7-12 


9-74 


13-62 


48-6 


,1 




„ 5 do. 


50 


83-6 


70-8 


62-8 


•564 


6-32 


9 03 


12-24 


49-2 


>, 



27 



HYGROMETER READINGS TAKEN IN JUNE 1894, TO COMPARE WITH 
THE FOREGOING TABLES TAKEN IN WINTER, 1892-3. 





Rooms. 


Counts. 


Hygrometer. 


Dew 
Point. 


Elastic 
Force. 


Weightof 
Vapour. 


Weight of 

Vapour 

if 

Satu ated. 


Humidity 
of Room. 


Humidity 




nry 
Bulb. 


Wet 
Bulb. 


room in 
Winter. 


«B" 
























Mixing 


— 


64-70 


55-50 


47-20 


•320" 


3^58g'-- 


6^80srs. 


51 % 







No. 4 Sping. 


120s 


86-0 


72-2 


62-9 


-573 


6^06 


1313 


464 


43% 




„ 3 do. 


110—140 


86-2 


71-9 


62-6 


-670 


604 


13^5 


45 


42 


"C" 
























Mixing 


— 


72-1 


61 


52-6 


-398 


4-39 


8-48 


51 







(Cards) end 


— 


770 


640 


549 


•431 


4^6 


8^9 


47 


36 




,, centre 


— 


/9 


65-1 


.55 6 


-444 


4^76 


10^63 


44 






No. 2 Sping 


60s 


89-2 


720 


61-2 


-539 


5-68 


1436 


38^6 


352 




„ 3 do. 


60s 


918 


72-3 


60-3 


-522 


554 


15 28 


35 


33-7 


ujy» 
























Mixing 


— 


66-2 


56-0 


47-8 


-."31 


3^68 


6^96 


51^4 







No. 2 Sping. 


60s 


93-4 


72-5 


59 8 


•514 


531 


16-33 


322 


31 




„ 3 do. 


60s 


97-8 


76-8 


646 


•608 


6-26 


18-36 


338 


30 



MILL IN RUSSIA PROVIDED WITH SPRAY HUMIDIFIERS. 

Ciird Room 

Combers 

Mules 



82-0° 


730° 


67^0° 


662" 


710gr 


ll-70gr 


87-0 


75-0 


67^3 


•669 


7^0 


13-60 


88-0 


74^0 


65^1 


•619 


650 


14^0 



60% 

52 

46 



The rooms of the mills in which the readings were 
taken, the numhers spun in each mill, the percentage of 
saturation of the outside atmosphere, the readings of the 
dry and wet bulb, temperature of the dew point, elastic 
force of aqueous vapour, weight of vapour per cubic foot 
of air, weight of vapour if air was saturated, vapour 
required for saturation of each foot of air, percentage of 
humidity, (saturation point = 100), will all be found in the 
table. 



28 

It will be seen from the foregoing tables that there 
is a considerable diversity in practice in mills spinning 
much the same numbers and presumably much under 
similar conditions. It will be further noticed there is 
not the difference popularly supposed to exist between 
the mills spinning extra fine and those spinning medium 
numbers. As a matter of fact, there are no large modern 
mills spinning very fine. This trade, such as it is, lies 
pretty well in the hands of old established firms in 
possession of ancient buildings which, although ancient, 
are suitable for this class of work. It is, of course, 
within tbe knowledge of all interested in the cotton trade, 
that numbers, in the last twenty-five years, have become 
gradually coarser, on the average, for better classes of 
yarn ; the explanation of this being that improvements in 
the exactness of process has enabled, in many cases, 
single yarn to replace doubled yarn of twice the fineness ; 
if not as perfect in result at least as perfect as the 
competition in the article manufactured requires. Thus 
the standard 60's twist of to-day replaces the 120's 
doubled of 25 years ago. 

I will now give an interesting comparison of a typical 
mule room, the temperature at which the mills were 
working, weight of aqueous vapour which the limit of the 
Act of Parliament permits in weaving mills, weight of 
water it would represent if condensed, the relative humi- 
dity being given in each instance, compared with the 
same quantities existing at the time the observations 
were being made in four mills. 



29 



«w 









C3 



o o 
o o 

OC (M 

O CO 
-^ CO 
CO iM 



o 00 

00 00 

X t~ 

CO >-( 



o o 

CO 00 
to C5 

id o 

>o o 



s s i 

o ci,t3 
£ > a 

c8 o:z: 









^ 



o 


.ti 


-.J 


01 


a 


a 








1 


0) 






l-i< 




eS 




o3 


<1J 


n 


s 


a 


r> 


*-" 


S 


A 


03 


H 


> 


^ 


*^ 


X 




m 


a 


^ 



fe 



2 a 



£ ^ =* 

s §•=* 



O ~K 

00 00 
CO 00 

CO t^ 

<M CO 



a> a. 



O) 3 S 

a s^=s 



o 



03 



Q c3 a; 



tjc 



o 


£> 




h 


a 


0) 


o 


fS 








rn 


c c 








: -^ 


d 



en 


rn 


rn 


C 


J3 


<u 


C 


C 








O 




eS J 




> 






M 


_^ 


ft« 




ja 


O 






(U 


TS 




^ 


a 


d) 


■*^ 


eS 




tfT-^ 


3t5 


a 


r?-* 


0) 


o 




J= 


■^ 






o 


_o 


o 


tn 




a 


>5 


3 g 


cS 

to 


03 


6C 










O 

<D 

3 


a 
a 

S, 




:» 


<i> 


<1 


03^ 



ID O JS 



^tSH 



30 




13. 



C." 



31 



I give also a reproduction of photo-micrograph show- 
ing yarn spun in mills "A," "B" and "C"; all being No. 
60's twist. It will be seen that yarn " A " is a more solid 
and regular thread than the others. I may say that 
its test hi strength bears out this. 

I have to call special attention to this illustration 
because although the zincograph does not give quite the 
whole of the detail of the photograph, it shows sufficiently 
clearly the enormous difference existing. This difference 
is quite as noticeable and striking in the whole of the 
photographs that have been taken, that selected being 
considered a fair average of the others. 

The following table will show a microscopical test, 
from which may be clearly deduced the superior regu- 
larity of yarn in mill '*A", the different mills being 
named by letters, "A," ''B," "C." 

MICEO-MEASUREMENTS OF THE DIAMETER OF THREE 
SAMPLES OF YARN. 



MICROMETER LINES = g^ INCH. 



'A"— 60's T. 
No. of lines. 



9 


9 


8 


9 


9 


9 


8 


8 


8 


8 




8 


7 


9 


11 


9 


9 


10 


9 


8 


10 


7 


10 


7 



Mean — 8Jf 
Range of 4 lines. 



"B"— 60's T. 
No. of lines. 



11 
11 
10 
12 
11 
10 
12 
12 
13 
12 
10 
9 



13 

11 

11 

10 

8 

9 

8 

13 

14 

11 

12 

10 



Mean = 10|| 
Range of 5 lines. 



C "—60's T. 
No of lines. 



14 
12 
13 

18 
14 
13 
19 
13 
14 
19 
13 
17 



20 
16 
13 
12 
14 
14 
17 
12 
22 
20 
19 
21 



Mean = 16 
Range of 10 lines. 



32 

From the table of comparison of the fonr typical 
mills on page 29 it will be seen that the mill "A" 
approaches, in percentage of humidity, more nearly the 
Act of Parliament than any of the otliers ; and this, in- 
deed, is the only difiference that will explain the smooth- 
ness and roundness and superior regularity. Of course, 
the instances given are only typical, and carefully 
selected as fairly average cases. I believe I can guar- 
antee their exactness. 

Having now endeavoured to show the importance of 
this question of humidity, its relation to electricity, and the 
want of similarity in practice, I will proceed to describe 
the different methods adopted for the purpose of 
regularising the moisture of the air, their success or 
otherwise, and, finally, give an opinion as to the 
temperature and humidity most desirable, and the simplest 
and easiest method of accomplishing this. 

UTILIZATION OF NATURAL EVAPORATION. 

The simplest method of increasing the humidity of 
the air in a room is by sprinkling water upon the floor 
and trusting to the natural evaporation which, of course, 
is more speedy with high temperatures than with low. 
This is known, in Lancashire, as " degging," and is 
practised to an extent hardly thought of, especially in 
manufactories unprovided with more perfect systems — 
more perfect only as referring to its automatic supply, 
because evaporation from a regularly sprinkled floor 
secures a diffusion of humidity, the regularity of which 
cannot be surpassed. But the system is troublesome, 
requires manual labour, is dependent upon the exactness 
of an individual, and the continual dampness of the floor 
is often supposed to cause rheumatic afflictions to the 



33 

workpeople. Again, in some weaving sheds, channels 
have been made in the floor which have been partially 
filled up with bricks, making a perfectly level surface, 
with interstices. These channels drain down, generally, 
to one end or side of the room and the water is allowed 
to flow through the channels, the idea being that the 
bricks will absorb the water and render it, by evaporation, 
to the room. Further, these channels have, as a rule, 
been taken under the looms. The writer much doubts, 
however, if they are kept in actual operation in those 
places where they have been constructed, the reason for 
this being that the tacklers object to tackle the loom and 
having to lie on their backs upon the damp bricks. 
Further, the interstices between the bricks or tiles soon 
get made up with the dirt and waste from the floor ; and 
as the thorough cleaning periodically would be a consider- 
able labour it is simply left undone. If the surfaces of 
exposure were sufiicient, the required amount of humidity 
could well be gained by this system, which would be satis- 
factory — apart, of course, from its practical objections. 

Another method of utihsing natural evaporation, and 
one free from the objections named in the above remarks 
is that of shallow water troughs making the circuit of the 
room or crossing at different distances according to 
requirements, the surface exposure of the troughs bearing 
a relation to the cubical content of the room to be 
humidified. These troughs are sometimes placed over 
the heating steam pipes, at other times underneath, and, 
occasionally, suspended from the ceiling joists without 
reference to the position of heating pipes. In every 
case the water is allowed to enter at one end of the room 
and to flow, by gravitation, slowly along the troughs to 
the other extremity, where the water is collected for 
re-use, or for some other purpose. But this, after all, is 



34 

unimporfeant, the maiu object being to supply the water 
at about the temperature of the room, and by sufficient 
motion to allow the globules to be successively subjected 
to the absorbing power of the air. 

To deal with the advantages or disadvantages of these 
three arrangements, I may say that where the troughs 
are placed over the steam pipes they can be carried by the 
pipes on brackets, and, as the steam pipes themselves are 
generally regulated with a view of allowing the water 
formed by condensation to gravitate to one extremity, the 
troughs will also follow this inclination. The pipes being 
underneath, the heat radiating has, of course, a tendency 
to increase the natural evaporation. When the troughs 
are suspended from the heating pipes the radiation also 
acts upon the evaporation, and the troughs themselves form 
a shield to prevent the direct rays of heat from affecting 
the workpeople. * When the workperson has to stand directly 
under the steam pipes, headache and nausea are often 
produced. This would seem to be, then, in favour of this 
system. Moreover, any leakage from the joints of the 
steam pipe would fall into the trough instead of on to the 
floor. Wliere the troughs are placed near the ceiling, 
they have the advantage of not interfering with the 
passage of hght to such a degree as when in other 
positions, and, also, of being in that part of the room 
where the heat is greatest and, consequently, the evapora- 
tion most active. 

There are partizans of each of these systems, but, as 
they can all three produce practically the same result, I 
will leave the matter as one of taste, only remarking, that 
in considering this, the height of the room must be 
taken into account. 

* As between the positions of the trou;,'h above the stciiui pipe and unaerni ath, the relative evaporation 
is:— above, 0-39in.; below, 46in., showing, an advantage in evaporation in favour of the troughs being 
beiow, in addition to the further advantages enumerated. 



35 

The foregoing represents, briefly, all that has been 
done in ntilising the principle of natural evaporation. 

AETIFICIAL METHODS OF PRODUCING 
MOISTURE. 

We have now to consider the artificial methods of 
producing moisture. In all systems the water, contained 
in the air in a state of suspension, is either a chemical or 
mechanical mixture. What I would say is that natural 
evaporation means general diffusion and intimate and 
atomic assimilation. Air and water so assimilated have 
no tendency to separate until the conditions of temperature 
or pressure have necessitated it. 

Now in all mechanical appliances for distributing 
fine particles of water in a proportionate quantity of 
atmosphere, there is a limit to the power of atomization 
or pulverization ; and, no matter what pressure be used, 
the sub-division into particles is infinitely inferior in 
number to the result of natural and free evaporation. 
Therefore, any system of this kind, whatever its name 
may be, can only be relatively advantageous as compared 
with natural systems. If we take another illustration — 
in a case where spray and vapour are produced by physical 
force, such as vapour rising from the ground during an 
excessively heavy rain storm, or the spray formed by a 
gigantic waterfall — it will be found that the efl^ect of 
the humid air is confined to a short radius round the 
centre of action ; but wdiere the rising sun, heating damp 
ground causes a mist this does not fall in the shape of 
rain or dew, but is gradually absorbed owing to the 
increasing elastic force of aqueous vapour. I hope this 
will make plainer my remarks with regard to the difference 
between chemical and mechanical moisture and afford 
further proof of the advantage of the natural method. 



36 

Thus it is found by absolute observations that the 
conditions of moisture in a room naturally humidified is 
very much more equal than in any mechanical system. 
This is explained by the facility with which natural 
vapour can be assimilated by the neighbouring air, as 
opposed to the mechanically powdered water ; and may be 
illustrated by an example in chemistry where in a perfect 
chemical solution it is possible to continue dilution until 
the absorbed substance is one part to a million. In a 
simply mechanical mixture the limit of dilution is quickly 
reached. Thus all systems, which have, for principle, the 
pulverization of water, have the initial defect I have 
alluded to ; and they can at best be but a rough and 
ready w^ay of attempting to solve what is, after all, a 
simple problem. 

EQUABLE HYGROMETBIC CONDITIONS. 

In this regard I have some observations which show 
how impossible it is to arrive at equable hygrometric 
conditions with mechanical methods. The apparatus 
employed w^as, perhaps, one of the best of the mechanical 
systems ; the room was 150 feet by 50 feet, the height 
about 13 feet, and the apparatus was placed about 15 
inches from the ceiling. The action of the apparatus 
was also assisted, as regards diffusion, by ventilating 
tubes, which introduced fresh air at many points in the 
room. 

No. 1 room showed the humidity of the air to be, at 
10 inches from the apparatus, 95 per cent ; at 3 feet away, 
the mean of a number of observations showed 75 per cent, 
of humidity, at 12 feet away from one instrument it was 
nearly CO per cent. In these cases, the temperature close 
to the apparatus was 60 deg.; 3 feet off, 63 deg.; and 12 
feet distant 71 deg. — showing, in addition to the differ- 
ence in hinnidity, a considerable range of temperature 



37 

in the same room. There was, also, a well defined, but 
inexplicable range of percentage of humidity 3 feet away 
from the instrument, the range being no less than 12 per 
cent from 11 o'clock to 1-40. This might be traced, no 
doubt, to some accidental current of air. But more 
extraordinary was the fact, absolutely proved, that in 
10 minutes the temperature varied from 63-2 deg. to 
65 deg., and the percentage from 77 to 68. At the 
farther end of the room, 5 feet from a blank wall, with no 
door or opening, the temperature changed, in 20 minutes, 
from 68-4 deg. to 71 deg. and the percentage of humidity 
from 621 to 56. In a similar room, but without 
humidifiers, the observations showed a range of tempera- 
ture of 4-2 deg. and 9 per cent, of humidity. The 
variation would not have been so great as this but for 
the fact that there were open windows at one end, 
which decreased the percentage ; but the readings of the 
observations were generally more equable. The tempera- 
ture of the atmosphere outside was 47-3 deg. and the per- 
centage of humidity 67. 

As a further proof of the inefficiency of this system 
of humidifying, I point to the fact that it is not practicable 
to place this apparatus near moving bodies, such as 
driving straps or shafts. In any case, where there is an 
induced current of air, precipitation takes place. To 
such an extent is this so, that the apparatus has had to be 
moved from the centre of the room to the sides, to avoid 
the action of the shaft and straps upon the air. 

OBSERVATIONS WITH AND WITHOUT 
HUMIDIFIERS. 

I think it will prove useful to here append reproduc- 
tions of photo-micrograph typical of woollen yarn spun, 
with and without humidifiers on the day the observations 
were taken. 



38 




ORDINARY X 40. 



HUMIDIFIED. 



39 

It will be noticed that as iu the photographs of the 
cotton yarns, the same result is apparent. That is to say, 
the yarn spun under moisture is more solid, consistent, 
and regular. The examples given were spun from the 
same preparation, out of the same wool and the same 
numbers ; although this is difficult to believe from the 
photograph — multiplied 40 diameters.* 

To make even still clearer to the eye the extra- 
ordinary difference in the compactness of the fibre under 
operation iu the various conditions of humidity or 
dryness, I give another photographic illustration (see 
page 40) of woollen sliver multiphed 20 diameters ; 
No. 1 worked in the ordinary air of the mill, and 
No. 2 in a room provided with humidifiers; the 
numbers, fibre, speed of machines, and every condition, 
except the humidity, being precisely alike. 

In a visit to the United States, where, as I have said 
previously, this question is one of great importance and 
where many inventions have been tried, I had an 
opportunity of inspecting various systems. I state 
unhesitatingly, there was more or less precipitation in 
every case of mechanical humidification. This will be 
easily comprehended when I remark that, in a state of 
the slightest motion, air will not carry a greater weight 
than 80 per cent. And the quicker the motion of the air, 
the greater the precipitation. 

I scarcely know whether it would be time well 
spent to discuss the bearings of the question of live 
steam admitted in the working rooms. There may be 
manufactories whore such a course is necessary, but I 
do not know of any; and most certainly spinning and 
weaving are not in the category. As has been pointed 

* Whilst correcting the final proofs I liave been again struck witli the remarkable difference shown in 
the photograph as between tlie two yarns. I can only attribute it to the fact that the magnified nhotoeranh 
snows, and perhaps may ex^gfjerate, tlie pecuUar difference really exislinK- One thing I will guarantee is 
that these yarns are fair samples of the bulk and that no attempt has been made to enlarge the differenrp 
lor the sake of effect. »>i<.ciii,c 



40 




ORDINARY X 20. 



HUMIDIFIED. 



41 

out previously in this paper, live steam will increase 
rather than diminish tlie electrical difficulty, particularly 
with wool stock much more than with cotton. It is 
exceedingly unpleasant to the persons working in the 
room ; and, I think it is generally admitted, very 
injurious to their health. It is therefore undesirable, 
from every point of view; and as proper conditions of 
the air can be so easily arranged in other ways there 
would seem to be little excuse for a continuance of 
this practice. I am glad to say that, personally, I do 
not know of any mill in this country where such a 
practice obtains, although I have seen it often enough 
abroad. 

MECHANICAL versus NATURAL HUMIDIFIERS. 
Taking into consideration the cost of the plant, 
the power, the cost of supervision, the cost of replace- 
ment and repairs necessitated where artificial humidifiers 
are employed, and, above all, the inefficiency and 
inequality of the result as compared with the system 
of evaporation, I feel justified in declaring that, in 
my opinion, the cheapest, most efficient, most regular, 
and simplest method of maintaining a constant degree 
of humidity in an enclosed body of air is the application 
of some simple system of natural evaporation. 

That it may be clearly understood what is to be 
done to arrive at the best result for practical working 
in cotton mills, I give a carefully prepared table showing 
the readings of the dry bulb and the wet bulb, together 
with the degree of humidity best calculated for the 
thoroughly good working of the material operated upon. 
It will be found that the results are much under those 
allowed by the Cotton Cloth Factories Act of 1889. 
Thus, take 90 degrees. The utmost humidity necessary 
would be 49 per cent, as against 69 allowed by the Act ; 



42 



at 80 deg. it would be 52 as against 77*5 ; at 70 deg. 
53 per cent, as compared with 88 ; and at 60 deg. it would 
be 54 per cent, as against 88 per cent, allowed by the Act. 
Thus leaving out the question of weaving sheds, which 
require more humidity than spinning mills, cotton 
spinners will see they have absolutely nothing to fear 
if working under this Act of Parliament. 

Humidity, and weight of vapour per cubic foot, for Spinning Kooms. at temper- 
atures varying from 100'' to 40° F, and the temperature at which the 
"Wet Bulb" Thermometer should read to attain it: — 



Dry Bulb. 


Relative 
Humidity. 


1000 


46% 


99 


46 


98 


47 


97 


47 


96 


47 


95 


48 


94 


48 


93 


48 


92 


49 


91 


49 


90 


49 


89 


50 


88 


50 


87 


50 1 


86 


51 ' 


85 


51 


8i 


51 


83 


51 


82 


51 


Si 


51 


80 


52 


79 


52 


78 


52 


77 


52 


76 


52 


75 


52 


74 


52 


73 


52 


72 


52 


71 


53 



Weight 






Relative 
Humidity. 


Weight 




of Vapour 
Grains. 


Wet Bulb. 


Dry Bnlb. 


of Vajwur 
Grains. 


Wet Bulb. 


9-2 grs. 


85-50 


700 


53% 


4 3 grs. 


60-00 


9-0 


84-0 


69 


53 


41 


59-0 


8-8 


83-6 


68 


53 


41 


58-3 


8-6 


82-3 


67 


53 


3-9 


57-3 


8-3 


813 


66 


53 


3-8 


56-3 


8-3 


81-0 


65 


53 


37 


55-5 


8-0 


80-0 


64 


53 


3-5 


54-5 


7-8 


790 


63 


54 


3-4 


53-7 


7-7 


78-6 


62 


54 


3-4 


530 


7-6 


77-7 


61 


54 


3-2 


52-0 


73 


76-7 


60 


54 


3-1 


51-0 


7-2 


76-3 


59 


54 


31 


50-3 


70 


75-3 


58 


54 


30 


49-3 


6-9 


74-6 


57 


54 


28 


48-3 


6-6 


73-5 


56 


54 


2-7 


47-5 


6-5 


72-6 


55 


55 


26 


46-7 


6-3 


72-0 


54 


55 


2-6 


46-0 


6-1 


710 


53 


55 


2-5 


45-0 


5-9 


70-0 


52 


55 


2-5 


44-3 


.5-8 


69-3 


51 


56 


2-4 


43-5 


5-7 


68-6 


50 


56 


2-3 


42 5 


5-5 


67-7 


49 


56 


2-2 


41-7 


5-4 


66-7 


48 


57 


2 2 


41-0 


5-2 


65-7 


47 


57 


21 


40 2 


5-1 


65 


46 


57 


2-0 


39-2 


4-9 


64-0 


45 


57 


2 


38-4 


4-7 


63-0 


44 


58 


2-0 


37-8 


4-6 


62-3 


43 


58 


1-9 


36-8 


4-5 


61-3 


42 


58 


1-8 


35-6 


4-4 


61-0 


41 


58 


1-7 


350 






40 


58 


1-6 


34-2 



EVAPORATION. 

In considering the (]uantity of water that should be 
evaporated to produce the wished-for result in the 
condition of the air it became necessary to experiment 
as to the rate of evaporation at varying temperatures 
and to endeavour to find a practicable working mean 



43 

that would simply require ordinary attention to maintain 
the degree looked for. The mule rooms in mills of 
to-day are built wider and higher than those in the 
old factories. This necessitates an increased degree of 
evaporative power. The condition of the exterior, 
atmosphere requires to be still considered, and the 
more this varies climatically, the more perfect should 
be the apparatus to enable any requisite adjustment 
to be made without unnecessary loss of time. Thus 
in an east wind, any air admitted — which, of course, 
is a constant occurrence, so long as work is going on — 
reduces the temperature of the air in the room and 
absorbs a proportion of the moisture, lowering the 
general average. In winter, when the air admitted 
might be fully saturated, introduced at, say, 30 deg., and 
being saturated with some two grains of vapour per cubic 
foot if raised to 80 deg. requires about 11 grains per cubic 
foot to complete saturation ; thus calling for a moisture of 
5| grains per cubic foot in the room to raise it to the 
temperature and humidity requisite. This, and the fact 
that the material itself is constantly absorbing some of 
the existent moisture and that there is an inevitable 
condensation constantly proceeding upon the windows 
and upon the walls, requires that a quantity of vapour 
should be replaced continuously. To effectually provide 
for this is the problem I have had to solve. 

It is nearly impossible to quote figiu'es of any 
exactness to show the loss occasioned by the before- 
named conditions — climate, position, elevation, exposure, 
the nature of the building itself, the thickness and 
fitting of the windows, the facility for the admission 
of air through the doors, and the number of times that 
the doors are opened, are all factors varying in different 
mills, and it would be difficult indeed to lay down any 
hard and fast rule. 



44 

Further, in considering the question in rehition to 
the percentage of humidity desired, it must be borne in 
mind that the temperature of the room is an important 
factor in determining the amount of water surface necess- 
ary to obtain the deficiency of vapour. Thus the higher 
the temperature the more difficult it is to maintain the 
percentage of humidity desired, and, therefore, the 
greater the evaporative area requisite. For instance, 
under similar conditions as between 81 degrees and 92-3 
degrees the evaporation in the same time was, for the 
lower temperature 0*14 inches and for the higher 0-295 
each 24 hours. 

This, of course, was simply an experiment in one 
portion of the room under ordinary working conditions ; 
but applied to the whole of the room the difference would 
be more marked on account of the greater surface of 
walls and windows conducing to condensation. 

It may be interesting to show how the experiments 
with regard to evaporation were conducted. In the first 
place, they were all taken in an ordinary cotton mill 
working under supposed normal conditions. A 5in. 
evaporator was exposed in each position for 48 hours. 
There were self- registering maximum and minimum 
thermometers placed in close proximity and the readings 
noticed each day the instrument was exposed. The 
reason for the Sin. evaporator being used was to facilitate 
the accurate measurement of the water evaporated by 
means of the certified 5 in. rain gauge of the Meteorologi- 
cal Society. The same iustruments were used throughout. 
The proportion of evaporation between the 5 in. gauge 
and one foot square as directly proportioned to their 
surface was rather over seven to one. 

In taking the capacity of the rooms in modern mills 
and estimating the average temperature customary, it 



45 

may be fair to assume that the humidifying plant should 
not have less capacity than that indicated by the evapora- 
tive observations taken under normal working conditions 
in order to maintain the standard amount of moisture 
necessary for successful operating of the cotton. This, 
carried a little further, and granting that a temperature 
of 90 degrees Fahr. would be the extreme mean tempera- 
ture at which the room might ever be heated — which, 
it is hardly necessary to say would allow a considerable 
margin for contingencies — it would require 3,552,120 
grains of aqueous vapour to give a humidification of 
50 per cent, in an ordinary mule spinning room of a 
capacity of 360,000 cubic feet. 

Now even in our humid climate in those mills 
possessed of no artificial means of humidification it is 
found that there are only some two million grains of 
vapour present at a temperature of about 90 degrees. 
The problem is, therefore, to introduce into the air 
in this room about one and a half million grains more 
vapour and to maintain that amount. 

This means, shortly, that each 24 hours 205 lbs. 
of water should be evaporated. Thus, taking the 
ordinary mule room and the ordinary amount of 
evaporation at 90 degrees as 2-163 inches per superficial 
foot, it would require 758 feet of water surface to supply 
the difiiciency. 

In spinning rooms working at a mean temperature 
of 90 degrees, a trough of water placed 9 feet from the 
walls round the room, 15 inches wide at the top and 
reduced by 2 in. steps as shown on page 47, would have an 
area of water surface of 785 superficial feet. This I 
believe would be the maximum required for humidifying 
under the most adverse climatic conditions. 



46 



?5?s^-»^t^vvv;^v^v^^~t^^^ss^svsss^^^^^ 



y^.,^..r 



rTU 



^ 




^^^^^S^S^S^S^^SE^ 



;^^;^^^^^^^S^SSS^^^^S^^^^S^^ 



^^ 



47 




A 




B 




C 



JH 



.5' 



48 

The illustration on page 46 shows a mule room 
with the position of the steam pipes and evaporation 
troughs. On page 47 various sections of troughs are 
shown. The forms "A" and "B" are in practical use in 
some mills; the one marked "C" has not heen tried 
practically but is a suggestion of a method for securing 
uniform evaporative surfaces throughout the area of the 
room^ the theory being that if there is only one inch 
of fall from the beginning to the end of the troughs 
it will be possible to keep the level of tbe water in the 
troughs between the limits of one of the steps, thus 
maintaining a constant surface exposed throughout the 
room and permitting of a measurable grading of the 
amount of evaporation. 

No other shape of trough except this stepped one 
can be relied on to give equal results in all its leugth. 
The trough is a suggestion of Mr. Midgley, Observator 
to the Bolton Corporation, and is the outcome of con- 
siderable thought and experience. Naturally there 
must be a supply and exhaust tap for each system of 
troughs. The method of supply and the dealing with 
the waste water are subjects that are outside this paper 
but will no doubt be intelligently dealt with in every 
case. It is suggested there should be a 2in. supply 
and a 2in. exhaust tap in order to allow speedy adjust- 
ment of the evaporation and that the continuous supply 
should be by means of a fin. bye-pass for the normal 
current. A natural suggestion would be that the water 
should be raised to the top of the building and allowed 
to descend from room to room by gravity. 

CaNCLUSION. 

In the card-room, working at a mean temperature of 
80 deg. or less, it would require 502,320 grains of vapour 
more than exists ordinarily. This would be secured 



49 

by a superficial area of water surface of 560 feet. A 
trough 9in. wide, (as shown on page 47, and marked 
''D") diminished lin. each step, would fully supply the 
deficiency. 

A modern spinning mill equipped with the above 
described apparatus and a certified hygrometer should 
have no excuse for not being in the very best hygro- 
metrical conditions for working the fibre to the very 
best advantage. Seeing the extraordinary importance 
of this portion of the industry it is to be hoped that 
more attention will be paid to the matter than there 
has been hitherto. The hygrometers should be read 
two or three times a day and the temperature of the 
dry and wet bulbs, together with the percentage of 
humidity, entered in a register for the inspection of 
the management. If this be done systematically and 
carefully the average quality of the yarn produced in 
this country will be improved; less cotton will be lost 
in invisible waste and fly, and complaint of brittle, 
hairy or "oozy" and uneven yarn should become a 
thing of the past. 

In the compilation of the whole of the foregoing 
I have to most heartily acknowledge the very great 
assistance I have received from Mr. Midgley. The 
shortness of this paper and the condensed information 
can hardly give an idea of the enormous amount of 
labour that has been necessary to arrive at reliable 
results. For myself I have had only one object, namely, 
to throw as much light as I could upon what seemed 
to me to be a terra incognita, and to assist, to the 
best of my ability, the trade of cotton spinning in 
which I am so deeply interested. 



* 



G. S. Heaton, Victoria Piunting Works, Bolton. 



3 2922 00388 114 8 



WM 



^^rkMii^i^¥a^l\ 



L;Pi:.C. COLL TS1577.D65 1894 
^ Dobson, B. A. 
^ Humidity in cotton spinning 




Q 



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