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scious and automatic, the faculties of them
being organised in the constitution of the nerve
centres, and they being then performed as reflex
effects of an external stimulus. This, as we
shall see, is a most important law in the develop-
ment of the higher nerve centres.

and properties that are the very foundations of
its development in the higher centres. Some
eminent physiologists now maintain, on the
strength of these experiments, that the accepted
doctrine of reflex action is quite untenable, and
that the spinal cord is really endowed with sen-
sation and volition; and certainly these adapted Let us now go a step further. The automatic
actions seem to give us all the signs of being acts, whether primary or secondary, in the
felt and willed, except telling us that they are so. frog or in the man, which are excited by the suit-
Before accepting, however, this explanation of able external stimulus, may also be excited by an
the obscure by something more obscure still, it act of will, by an impulse coming downwards
were well to realise distinctly how dangerous a from the brain. When this happens, it should be
practice it usually is to apply deductively to the clearly apprehended that the immediate agency of
interpretation of simple phenomena ideas per- the movements is the same; it is in the motor
taining to the more complex, and how essential a centres of the spinal cord; the will does not and
principle of the method of induction it is to cannot act upon the nerve fibres of each muscle
follow the order of evolution, and to ascend individually, but simply gives the order which
from the interpretation of the simple to that of sets in motion the organised machinery of the
the complex. The explanation savours of the movements in the proper motor centres. This is
old and evil tendency which has done so much a consideration of the utmost importance, for it
harm in philosophy, the tendency to explain the exhibits how great a part of our voluntary acts is
facts of nature by what we feel to go on in our really the automatic action of the spinal cord.
minds; because we know that most of our The same movements are effected by the same
actions take take place consciously and volun- agency in answer to different stimuli-in the one
tarily, we can hardly help thinking that it must case to an external stimulus, in the other case to
be the same in the frog. Might we not, however, an impulse of will; and in both cases the mind is
as well suppose and hold that positive attracts alike igaorant how they are done. But while the
negative and repels positive electricity consciously automatic acts take place independently of will,
and voluntarily, or that in the double decomposi- the will is absolutely dependent on the organised
tion of chemical salts one acid chooses voluntarily experience in the cord for the accomplishment of
the other base? It is most necessary to be on its acts; without this it would be impotent to do
our guard against the danger of misapplying ideas a voluntary act. When, therefore, we have taken
derived from internal observation of the functions out of a voluntary act the large part which is due
of mind centres to the interpretation of the to the automatic agency of the motor centres, it
functions of lower nerve centres, and so of mis- clearly appears that we have subtracted no small
interpreting them. Assuredly we have sad ex-proportion from what we are in the habit of com-
perience enough to warn us against involving the prising vaguely under mind. We perceive, in-
latter in the metaphysical haze which still hangs deed, how indispensable an exact and faithful ob-
over the functions of the supreme centres.
servation of the functions of the spinal cord is to
a true physiological inquiry into mind, and what
an important means of analysis a knowledge of
them yields us. Carrying the knowledge so gained
into our examination of the functions of the
higher nerve centres, we observe how much of
them it will serve to interpret. The result is that
we find a great part of the habitual functions of
the higher centres to be similarly automatic,
and to admit of a similar physiological interpre-
tation.

All the conclusion which the facts warrant is that actions for a definite end, having indeed the semblance of predesigning consciousness and will, may be quite unconscious and automatic; that the movements of the decapitated frog, adapted as they are to secure its well-being, are no more evidence of intelligence and will than are the movements of coughing, sneezing, and swallowing

in man.

displays of instinct, through sensory and associated motor nuclei. They seek what is good for. them, avoid what is hurtful to them, provide for the propogation of their kind-perform, indeed, all the functions of a very active life without knowing that they are doing so, not otherwise than as our pupils contract to light, or as our eyes ac commodate themselves to vision at different distances without consciousness on our part. The highest specialisations of this kind of nerve-function are displayed by the ant and the bee; their wonderful instinctive acts show to what a degree of special perfection sensori-motor action may be brought.

Unlike the bee and the ant, man must slowly learn the use of his senses and their respondent movements. This he does by virtue of the fundamental property of nerve centres, whereby they react in a definite way to suitable impressions, organically register their experience, and so acquire by education their special faculties. Thus it is that many of the daily actions of our life, which directly follow impressions on the senses, take place in answer to sensations that are not perceived become, so to speak, instinctive; some of them being not a whit less automatic than the instinctive acts of the bee, or the acts of the pigeon deprived of its hemispheres. When we move about in a room with the objects in which we are quite familiar, we direct our steps so as to avoid them, without being conscious what they are, or what we are doing; we see them, as we easily discover if we try to move about in the same way with our eyes shnt, but we do not perceive them, the mind being fully occupied with some train of thought. In like manner, when we go through a series of familiar acts, as in dressing or undressing ourselves, the operations are really automatic; once begun, we continue them in a mechanical order, while the mind is thinking of other things; and if we afterwards reflect upon what we have done, in order to call to mind whether we did or did not omit something, as for instance to wind up our watch, we cannot satisfy ourselves except by trial, even though we had actually done what we were in doubt about. It is evident, indeed, that in a state of profound reverie or abstraction, a person may, as a somnambulist sometimes does, see without knowing that he, sees, hear without There can be no doubt that the ganglionic knowing that he hears, and go through a series of nuclei of the senses-the sensorial nuclei-are acts scarcely, if at all, conscious of them at the connected with motor nuclei; and that we have time, and not remembering them afterwards. in such anatomical arrangement the agency of a For the most distinct display of sensori-motor acnumber of reflex movements. Most of the in- tion in man, it is necessary that his cerebral stinctive acts of animals are of this kind, the hemispheres, which are so largely developed, and faculties being innate in them. In man, however, intervene much in the functions of the subordi who is actually the most helpless, though nate centres, should be deeply engaged with their potentially the most powerful, of all living own functions, or that these should be suspended. creatures, when he comes into the world, the This appears to be the case in those brief attacks sensory and associated motor nuclei must be of epileptic unconsciousness known as the petit educated, just as the spinal centres must. To mal, in which a person will sometimes go on with illustrate this sensori-motor or instinctive action, the work he was engaged in at the time of the we may take the results of Flourens' well-known attack, utterly unaware of the momentary interexperiment of removing the cerebral hemispheres ruption of his consciousness. There are many of a pigeon. What happens? The pigeon seem- instances of this sort on record, which I cannot ingly loses at once all intelligence and all power stop to relate now; they prove how large a part I have taken the experiment on the frog to of spontaneous action. It appears as if it were sensori-motor functions, which are the highest exemplify the proposition that designed actions asleep; yet, if thrown into the air, it will fly. If nerve functions of so many animals, play in our may be unconscious and automatic, because the laid on its back, it struggles on to its legs again; daily actions. We ought clearly to apprehend phenomena are more simple in it than in man, the pupil of the eye contracts to light, and, if the the fact that, as with the spinal cord, so here, the and more easy, therefore, to be understood; but light be very bright, the eyes are shut. It will movements which take place in answer to the the proposition is equally true of his spinal cord. dress its feathers if they are ruffled, and will stimulus from without may be excited by the In its case, however, we have to bear in mind sometimes follow with a movement of its head the stimulus of the will descending from the hemithat faculties are not innate to the same degree movement of a candie before it; and, when a spheres, and, that, when they are so excited, the and extent as in the lower animals, but have to pistol is fired off, it will open its eyes, stretch its immediate agency of them is the same. The movebe acquired by education-to be organised, in neck, raise its head, and then fall back into its ments that are outwardly manifest are, as it were, fact, after birth. It must be taught, just as the former attitude. It is quite evident from this ex- contained inwardly in the appropriate motor brain must, before it can perform its functions as periment that general sensibility and special nuclei; these have been educated to perform an organ of animal life; and being much more sensations are possible after the removal of the them. Hence it is that, when the left corpus under the control of the more highly-developed hemispheres; but they are not then trans-striatum is broken up by disease, the right cannot brain, feeling and volition commonly mingle formed into ideas. The impressions of sense do its special work; if it could, a man might largely in its functions, and its independent action | reach and affect the sensory centres, but write with his left hand when his right hand was cannot be so plainly exhibited. But when its they are not intellectually perceived; and disabled by paralysis. motor centres have been taught, when they have the proper movements are excited, but these gained by education the power of executing what are reflex or automatic. There are no ideas, are called secondary automatic acts, it is certain there is no true spontaneity and the anithat it can and does habitually execute them mal would die of hunger before a plateful of independently of consciousness and of will. They food, though it will swaliow it when pushed far become as purely automatic as are the primitive reflex acts of the frog. To the statement, then, that actions bearing the semblance of design may be unconscious and antomatic we have now to add a second and most weighty proposition namely, that acts consciously designed at first may, by repetition, afterwards became uncon

In the constitution of the animal's spinal cord are implanted [the faculties of such movements for self-preservation, which it has inherited as a part of its nature, and without which it could hardly live a day; accordingly it acts necessarily and blindly; though it has lost its foot, it endeavours vainly to act as if its foot was still there, and only when the irritation continues unaffected by its futile efforts makes, in answer to it, those further reflex movements which are the physiological sequences of the unsuccessful movements: it supplements one series of reflex actions by another. But although these purposive movements are not evidence of intelligence and violition in the spinal cord, it is another question whether they do not evince the same physiological properties and the operation of the same laws of evolution as govern the development of intelligence and will in the higher centres.

*Two lectures delivered at the Royal College of Physicians in 1870. By HENRY MAUDSLEY, M.D., F.R.C.P., Professor of Medical Jurisprudese in Uni versity College, London.

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enough into its mouth to come within the range
of the reflex acts of deglutition. Here again,
then, we have a surprising variety of adapted
actions of which the body is capable without the
intervention of intelligence, emotion, and will
without, in fact, mind in its exact sense having
any part in them. The pigeon is brought to the
level of the invertebrata, which have no higher
nerve-centres than sensory ganglia, no centres of
intelligence and will, and which execute all their
varied and active movements, all their wonderful

Thus much, then, concerning our sensori-motor acts, When we have yielded up to the spinal cord all the part in our actions that properly belongs to it, and to the sensory ganglia and their connected motor nuclei all the part that belongs to them, we have subtracted no inconsiderable part from the phenomena which we are in the habit of designating mental, and including under mind. But we still leave untouched the highest functions of the nervous system-those to which the hemispherical ganglia minister. These are the fanctions of intelligence, of emotion, and of will; they are the strictly mental functions. The question at once arises whether we have to do in these supreme centres with fundamentally diff. rent properties and different laws of evolution from

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the square root of; the ultimate strain divided by depending on the increase of rigidness called forth
28, or if C circumference, B breaking by the force W.
Gerstner found all the values in Coulomb's
weight in tons :-
formula too great; we shall therefore find another
value for S.

B C2 X 28 C =

=

B

===

28

Table III.

Hemp.

Iron Wire. Steel Wire.

Equivalent

strength.

Circumference.

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those which belong to the lower nerve centres.
We have to do with different functions certainly;
but are the organic processes which take place in
them essentially different from, or are they iden-
tical with, those of the lower nerve centres ?
They appear to be essentially the same: there is
a reception of impressions, and there is a reaction Note-For common cables 28 may be replaced
to impressions, and there is an organic registra-by 2.
tion of the effects both of the impressions and of The following table* shows the weight and
the reactions to them. The external stimuli do strength of round ropes of hemp and wire:-
not, it is true, ascend directly to the supreme
centres as they do the spinal centres and the
sensory centres; they are transmitted indirectly
through the sensory ganglia; it is through the
senses that we get our ideas. This is in accord-
ance with the anatomical observation-which,
however, is disputed-that no sensory fibres go
directly through to the hemispheres, and no motor
fibres start directly from them; both sensory and
motor fibres stopping at the corpora striata and
thalami optici, and new fibres connecting these
with the hemispheres. But this does not alter the
fundamental similarity of the organic processes in
the higher centres. The impressions which are
made there are the physiological conditions of
ideas. The feeling of the ideas is emotion; for I
hold emotion to mean the special sensibility of
the vesicular neurine to ideas. The registration
of them is memory; and the reaction to them is
volition. Attention is the maintenance of the
tension of an idea or a group of ideas-the keep-
ing it before the mind; and reflection is the suc-
cessive transference of energy from one to another
of a series of ideas. We know not, and perhaps
never shall know, what mind is; but we are never-
theless bound to investigate, in a scientific spirit,
the laws of its functions, and to trace the resem-
blances which undoubtedly exist between them
and the functions of lower nerve centres.
(To be continued.)

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STRENGTH OF MATERIALS.
BY A. TOLHAUSEN, JUN.
(Continued from page 124.)

T is not every kind of tar that destroys the

and Stockholm are said to preserve the rope, so that in the execution of important works it is recommended that the ropes should have been recently manufactured, and be made of the best Petersburg hemp, with Archangel and Stockholm tar.

The tar applied to ropes made by the warm register is more fluid than in those made up with the yarns cold, and therefore penetrates every fibre of hemp completely. Again, as the heat drives off both air and moisture, each fibre is brought into closer contact by the twisting and compression of the strand, and the strength of the rope is greatly increased. Another advantage is derived from the warm register, as ropes made by the same are almost impermeable to water, so that it is absolutely necessary in places where they are exposed to the wear and tear of the weather to have them made by the new process.

The dimensions of ropes are generally 'stated in terms of their girth or circumference, and worked to about one-sixth of their breaking strain. The weight of hempen ropes (in lbs. per fathom) is approximately found by multiplying the square of their circumference by 26.

Flat ropes, made by placing four round ropes side by side, and stitching them up by machinery into a flat band, are now used for many purposes where great lengths or depths, such, for instance, as in raising coal from pits, have to be

attained.

34

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Table IV. shows the weight and strength of flat ropes of hemp and wire :

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RIGIDNESS OF ROPES AND STRAINS.
Till now we have considered
chains to be perfectly pliable, which, however, in
practice is not the case; for daily experience
shows that any rope of ordinary dimensions re-
quires a certain amount of force to be applied to
twist it in any direction, and this force is called
the stiffness, or rigidness of that rope.

It is obvious that this force will chiefly
depend on the intensity of that force W stretch-
ing the rope, on the radius of curvature, and the
thickness of the rope itself. Again, it will depend
on the material of which the rope is made, on the
number of fibres and twists given to the same, as
well as whether the rope is new or old, tarred or
untarred.

They possess great strength and flexibility. In some cases, if ropes were applied they would be cut to pieces in a very short time, and the Amontont and Coulomb (celebrated French weight of chains might also be inconvenient; it is engineer, born 1736 in Angoulême, and received in such instances that wire ropes are used, and the first prize of the Paris Academy of Sciences have proved to answer the purpose very well in for his Théorie des Machines Simples;" died working inclined planes, &c. On the Durham- in 1806) were the first who investigated this force, Sunderland railway, trains are drawn up and let and the experiments of the latter, which follow, down an inclined plane of 4 miles length by led him to the mathematical formula :means of an endless wire rope, made of three pieces.

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Should the diameter of a rope not occur in the

table, Coulomb gives the rule n multiply the next

approaching value by

72

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whereby is the

diameter of the rope whose rigidness is required,

The power n varies from 1 to 2, according to quality and strength of the rope.

The same found also that ropes, when moist, possess less rigidness when of large diameter, and greater stiffness when of small dimensions.

But although rope made by the warm register is both stronger and more durable, it is less pliable, and therefore the cold-registered rope is more generally used for crane-work, where the rope must be wound round barrels and passed through pulleys, as in these cases the radius of curvature is very small.

A formula more applicable to practical purposes is one proposed by Eytelweint and symbols lically demonstrated by

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The two practical rules for computing the strength of ropes are sometimes enunciated to Whereby S is the registry of the rope, & the dia-measures, the following may prove useful:-1 metre= meter of the same, r the radius of curvature; n 39-371in, and 1 kilogramme 22048lb. lin. = 00254 To find the breaking weight in tons of a rope an integer; a co-efficient, both varying with the met., aud 1lb. 04535 kilog. made of common hemp, multiply the square of quality of the rope, and b a magnitude merely the circumference (in inches) by 288; conversely

2 r

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ment, sometimes used in watches. A

MECHANICAL MOVEMENTS.

One pallet B, works in front of the wheel and the
other at the back. The studs are arranged in the
same manner, and rest alternately upon the front
or back pallet. As the curve of the pallets is an
arc described from F, this is a repose or dead-beat
escapement.

93. Duplex escapement, for watches, so called
from partaking of the characters of the spur and
crown wheels. The axis of balance carries pallet
B, which at every oscillation receives an impulse
from the crown teeth. In the axis A of balance-
wheel is cut a notch into which the teeth round
the edge of the wheel successively fall after each
one of the crown teeth passes the impulse pallet B.
94 and 95. A cylinder escapement. 94 shows
the cylinder in perspective, and 95 shows part of
the escape-wheel on a large scale, and represents
the different positions taken by cylinder A B
during an oscillation. The pallets a b c on the
wheel rest alternately on the inside and outside
of cylinder. To the top of cylinder is attached
the balance-wheel. The wheel pallets are bevelled
so as to keep up the impulse of balance by sliding
against the bevelled edge of cylinder.

105. A single-pin pendulum escapement. The escape-wheel is a very small disc with single eccentric pin; it makes half a revolution for every beat of the pendulum, giving the impulse on the upright faces of the pallets, the horizontal faces of which are dead ones. This can also be adapted to watches.

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two tools.

96. Lever escapement. The anchor or piece The framing of the machine consists of a B which carries the pallets, is attached to lever, central boss 1, made hollow to go over the head E C, at one end of which is a notch E. On a disc of the millstone spindle when operating on the secured on the arbor of balance is fixed a small bed stone, and this boss is connected by arms 2, pin which enters the notch at the middle of each to a segmental ring 3, accurately turned, or vibration, causing the pallet to enter in and retire otherwise made flat on its underside to rest on from between the teeth of escape-wheel. The the surface of the millstone 4, near the outer wheel gives an impulse to each of the pallets edge thereof, that being the part of the millstone

alternately as it leaves a tooth, and the lever
gives impulse to the balance-wheel in opposite
directions alternately.

97. An escapement with a lantern wheel. An
arm A carries the two pallets B and C.

surface that can be most relied upong of the truly level.

A

91. Arnold's chronometer or free escape To facilitate the placing spring A is fixed or screwed against the plate of the watch at b. To the under side of this spring frame on the stone three adjustable claws 5, are fixed on the segmental ring 3, and catch upon is attached a small stop d, against which rest the top binding hoop; accurate centering, howsuccessively the teeth of the escape wheel B; and 98. An old-fashioned watch escapement. ever, of the frame on the stone is not essential. on the top of spring is fixed a stud i, holding a 99. An old-fashioned clock escapement. Two of the frame arms 2, are made in the same lighter and more flexible spring which passes 100 and 101. A clock or watch escapement; line tangential to the boss, and to them there is under a hook k, at the extremity of A, so that it 100 being a front elevation, and 101 a side eleva- fixed a horizontal guide 6, made with V rails to is free on being depressed, but in rising would tion. The pallet is acted upon by the teeth of receive a saddle 7, which can be moved along the lift A. On the axis of the balance is a small stud a, which touches the thin spring at each one and the other of two escape-wheels alter-guide 6, by means of a screw spindle 8. nately. horizontal arm 9, is fixed to the saddle 7, so as oscillation of balance-wheel. When the move- 102. Balance-wheel escapement. C is the to stand out at right angles from the guide 6, ment is in the direction shown by the arrow, the balance; A B are the pallets; and D is the and this arm is made with horizontal V rails to stud depresses the spring in pissing, but on guide a slide 10, in which is adjusted the tool or returning raises it and the spring A and stop d, bort holder 11. The bort holder 11, is a spindle and thus allows one tooth of escape wheel to pass. screwed at its upper end to receive a nut, and letting them fall immediately to arrest the next. At the same time that this tooth escapes, another formed at its lower end with a cross plate to fit a rebate in the bottom of the slide 10, and with a strikes against the side of the notch g, and reboss in which a socket is bored to receive three stores to balance-wheel the force lost during a angular steel bits by which the bort is fixed. The vibration. It will be understood that only at one point is the free movement of balance opposed a cylindrical form a little less than the socket, three steel bits are shaped to build together into during an oscillation. and the bottom corners of their central meeting edges are hollowed to grip the bort, whilst they are adjusted upon it by screws tapped through the sides of the socket. With this simple con

92. Stud escapement, used in large clocks.

Extracted from a compilation by Mr. H. J. Brown Editor of the American Artisan.

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escape-wheel.

103. A dead-beat pendulum escapement. The inner face of the pallet E and outer face of D are concentric with the axis on which the pallets

vibrate, and hence there is no recoil.

104. Pin-wheels escapement, somewhat resembling the stud escapement shown by 92. The different forms, but the form of those on the right pins A B of the escapement wheel are of two side is the best. One advantage of this kind of escapement is that if one of the pins is damaged it can easily be replaced, whereas if a tooth is damaged the whole wheel is ruined.

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DRESSING MILLSTONES WITH THE DIAMOND OR " BORT."

are lifted for re-dressing they are found to be in perfect trim, having a beautiful straight level face, and with much of the former dressing still clear and distinct. One miller using Mr. Young's machine found, on a careful comparison with the results of the ordinary handbill dressing, that out of every hundred boll of wheat (1 boll 240lb.) he obtained a bag and a-half, equal to 420lb., more fine flour, with proportionally less seconds.

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points can be adjusted so as to cut accurately in | running six days and nights. When the stones
the same line. The two tools may also be
adjusted to cut in two separate lines if preferred.
A comparison with Golay's machine will
render obvious the superior construction of
Young's, its remarkable simplicity, and its free-
dom from various drawbacks associated with the
earlier machines. The dress or cracking which
Young's puts into the millstone, consisting of
straight horizontal cuts, is cleaner and neater,
and has not the ragged or fractured appearance
caused by the chipping action of the rotating A great variety of millstone dressing machines
tool. It is especially superior in indicating and have been brought out and patented since the se
discovering any inequality or want of truth in to which we have referred, but they are all com-
the grinding surface, doing this with a precision
and accuracy not hitherto attained, and which
necessarily arises from the machine being formed
with a turned bearing ring, which rests on a
large portion of the millstone surface near the
outer edge. This is confirmed in practice by the
machine discovering many imperfections of
surface which the prov-
ing staff allows to es-
cape notice. Requiring
no driving power, it
can be worked whether

struction the bort can be gripped in any position
by the steel bits, and the whole can be turned in
the socket so as to present the cutting angle of
the bort in the most advantageous manner. One
or two pieces of vulcanised rubber a are applied
between the bottom cross plate of the tool 11,
and the slide 10, and may be more or less com-
pressed to modify the elasticity of the tool by
means of the screw nut which holds the tool in
the slide. A handle 12, is jointed upon the slide
10, and by means of it the operator draws the
slide along the guide arm 9, and so causes the
bort to cut a minute groove on the surface of the
millstone. The dressing for one sector of the
millstone surface is done with the frame 1 2 3,
in one position, the arm 9, being shifted or fed
across after the formation of each groove by
means of the screw spindle 8. Toothed feed
wheels 13, are fixed on the ends of the
screw spindle 8, and are acted upon
by feed catches jointed to levers 14, set loosely
on the spindle and connected by means of a
horizontal rod 15, above. A handle 16, is set
loosely on the rod 15, so that it can be moved
into the most convenient position for the operator,
who works the tool slide 10, with one hand, and
the feed handle 16, with the other. The feed the mill is running or
may be effected either when the slide 10, is at standing. It requires
the inner end of its traverse, or when it is at the no gearing whatever,
onter end thereof, the bort being moved in both
directions along each groove; or the feed may be
effected both when the slide is at the inner end
and when it is at the outer end of its traverse, in
which case the bort will be moved only once
along each groove. When the dressing of one
sector of the millstone surface is completed the
entire machine is shifted round, to bring the arm
9, parallel to the grooves of the next sector.

Two borts with their holders may be carried
on the slide 10, as shown in Fig. 14; and this
modification may be used when a deeper cut is
required than that which a single bort will give,
one of the two borts being adjusted slightly lower
than the other. When applying two tools in
this way the spindles are fitted somewhat loosely
into the slide 10, and small cushions b of vul-
canised rubber are placed behind them, whilst
small pinching screws c are inserted in front,
and by turning these more or less the two bort

and is much less de

FIG.10

pendent on individual skill, as it can be
actuated by a lad or inexperienced workman. It
cannot get out of order. It dresses the stone in
less time than Golay's, and, as compared with
ordinary handwork, requires the service of fewer
stonemen. Immediately that the stone is set to
work after being re-dressed, it grinds perfectly,
making much fewer flour sharps, or middlings,
and, in consequence, a larger proportion of fine
flour. The bran is broader and better cleaned,
and the flour of purer colour and more regular.
The amount of feed, or rate of grinding, is not
decreased; whilst, in consequence of the ease and
rapidity with which the operation can now be
effected, the millstones are sometimes re-dressed
after running four days and nights. This more
frequent re-dressing is found advantageous where
the mixture of wheat is soft and tough, but where
it is dry the stones are re-dressed only after

prised in the "rotatory" and "rectilinear" classes, of which Golay's and Young's are respectively the chief representatives; and they differ amongst each other mainly as regards minor details, a critical comparison of which would not only be tedious and uninteresting, but it is also incapable of being satisfactorily made at present on account of the small experience as yet had with most of them.

Naturally, where several patented machines for the same purpose compete, questions must arise as to the novelty and validity of each, and as to whether the more recent are infringements of the earlier patents. The main competition is practically between the two most successful machines, Golay's and Young's; and we believe that the great hindrance to the more general adoption of one or other of these machines has been the doubt whether Golay's patent is valid, and whether Young's machine, as has been openly asserted by persons interested in Golay's patent, is an infringement of it. At the same time many of the most extensive millers in the United Kingdom have adopted one or other of the machines, convinced of the great superiority of the dress over hand dress. As regards the diamond itself, Golay does not claim to use the diamond except when acting with rapid blows, and clearly could not validly claim the plain, continuous, rectilinear cut of the diamond in face of the earlier patents of Childs and Knight; whilst as both Young and Golay are obliged to use bort instead of the common clear diamond, it is plain neither of them is clear of Jobin's patent. As regards the necessary apparatus, Young's only resembles Go'ay's

in having a horizontal guide and slide with a screw feed motion at right angles thereto; but in this respect both Golay's and Young's resemble Morisseau's, whilst Young's arrangement is in fact more like Morisseau's than it is like Golay's. We will not take upon us to certify how the lawyers will decide the questions, but they appear to us very simple ones, and plain common sense answers to them sufficiently obvious.

We have applied the term "bort" to the substance now used for dressing millstones, as being the best and most distinctive appellation without coining a new word; it is, however, also used to designate the impure fragments and excrescences which are removed from the rough diamond in the process of cutting, and which are not so hard or suitable as the stones originally found in a detached state.

THE END.

CAPTAIN PETERSON'S

IT

BOAT.

hours in ten ounces of cold water, and again dried
and weighed as before. This loss represents sugar,
theobromine, and other soluble constituents; and
it is evident that if sugar of adulteration be present,
the loss of weight will be greatly increased.
4. The residue (from 3) is boiled for an hour
in ten ounces of water, to which half an ounce of
hydrochloric acid has been added, and once more
dried and weighed. The loss in this case consists
of starch, cocoa red, &c., and here the starch which
has been purposely added is discovered.

5. A few grains of the cocoa are burned on a
crucible lid, and the colour of the ash is observed.
If this be decidedly red, then ochre or some such
colouring matter has been employed.

As we have already remarked, although the
process cannot pretend to absolute truth, yet a very
close approximation can be thus obtained, es-
pecially if samples of pure cocoa be first treated
in an exactly similar manner. This we have done
and the following results represent an average of
STEAM LIFE- several such experiments :-
Moisture

...

4.5

Now we are brought face to face with the question: Ought this addition of starch and sugar to cocoa to be regarded as an adulteration? If, on the one hand, we take the word adulteration to mean the mixing of anything hurtful or deleterious with an article of food, the answer must be in the negative, because not only is the starch harmless, but it supplies a want in the article itself, besides diluting its rich and somewhat dyspectic qualities. Indeed, this admixture has been regarded by an eminent food authority, as "a skilful chemical adjustment, made without chemical knowledge, as the result of long and wide experience." But, on the other hand, if we take adulteration to mean the mixing of anything (even if it should be beneficial) with an article of diet, withont distinctly setting forth the fact, the present style of cocoa manufacture becomes a sophistication. With the greatest desire to let this matter down gently, as we have no wish to hold almost all the cocoa manufacturers in England up to public reprobation as sophisticators, we connot escape the fact that many prepared cocoas are advertised as "genuine," nor can we help harbouring a shrewd doubt, that the comparative prices of cocoa and starch had much more to do with the "skilful chemical ad. justment," than a real desire to benefit the public. We should advise the many respectable firms engaged in the cocoa trade to call their cocoas such term as would convey the true impression of plainly and distinctly prepared cocoas, or by some their nature. This would be very much more sensible then denominating them genuine," "soluble," or "homoeopathic," &c., when all the connection they have with solubility simply conColour Chief Foreign sists in the amount of soluble matter added as a of Ash. diluent, and with homeopathy in the small amount of real cocoa which they give at a dose. In a word, we are once more brought back to the necessity for an "Adulteration Act," such as we have all along steadily advocated-namely, a law to compel everything to be sold under its own name, with proper officers to see the Act carried out; but to hope for such a thing under the present regime, seems almost Utopian; and we have no resource but to follow the dictum of an eminent statesman, and to "agitate and agitate."

48.5

11.8
18.8

Soluble in ether (fat)
Soluble in water (sugar, &c.)
Soluble in acid (starch, &c.)
Residue insoluble (cellulose, &c.) 16.4

-100.0

The colour of the ash was a light grey, and no foreign starch was visible under the microscope. With this explanation we proceed to the

5

Analysis of Thirty-one Samples of Cocoa.

ture.

Solu

In

Soluble in Solu- solu-
Cold ble in
ble
Ether Water Acid, (Cel-
(Fat). (Sugar Starch lulose.
&c.) &c. &c.)

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4.6
53.2 20:5 15.0 6.7
32 53.6 9.7 22.6 10'6
4.2 46-9 22.7 14.2 11-8
3.4 40.5 18.6 28.0 9:3
54 26.2 34.5 24.8 9:0
64 200 38.6 29-0 5.9
4-8 249 38.5 204
11:0
5:6 340
20.0 23.6 18:0
4.5 26.6 33.3 28.6 68

Grey. None

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11

T is said the invention of C. W. Peterson, of No. 7, Oakley-crescent, City-road, London, for the application of steam power to lifeboats, is destined to effect an important improvement in our lifeboat system, and consequently to increase very considerably the means at our disposal for saving life at sea. The Committee of the Shipwrecked Mariners' Society, after examining the models and drawings of the invention, have expressed themselves pleased with it, and are anxious that it should have an adequate trial. Captain Peterson is confident that his boat will be able to put to sea in all weathers, and that, if No Mois- ble in upset, it will instantly right itself without losing its motive power. The advantage it will possess, both in respect to increased speed and power, over the lifeboats now in use must, of course, be self-evident, but the great thing is to put the invention to the test. The cost of building a trial boat will be about £600 or £700, towards which the Committee of Lloyd's have subscribed £50, the Salvage Institution in £52 10s., the Shipwrecked Mariners' Society, £50, the Royal National Life-10 boat Institation £100, Miss Burdett Coutts £100 41 31.5 16.6 25.7 22:0 and about £50 has been contributed by merchants 12 5'6 82.4 20:3 2019 2018 and others, making altogether upwards of £400. 14 11-2 206 47.0 100 10.9 The names here mentioned as subscribers afford 15 4.5 27.1 35.2 25.9 7.2 16 5:0 21.0 38:0 300 60 a guarantee for the practicability of the proposal, 4.8 29.4 28.0 28.9 7.9 and we trust their liberality will at once be sup- 6.0 20-2 42.3 248 66 Red. plemented to such an extent as to insure the com68.4 19 64 39.5 395 plete realisation of Captain Peterson's intentions. 4.0 11.8 18.0 16-7 The object is one of such national importance that 22 71 11-6 38-8 87-0 5:1 it ought to command universal sympathy and sup-23 104 11.9 port, and to be received with special favour and 24 interest by maritime communities directly con- 261 cerned in the welfare and safety of our seamen. 27 This being so, Captain, Peterson may reasonably expect such an amount of assistance-and that, too, within a very short time-as will enable him to put his invention to the test.

We should like to know what Mr. Lewis, the zealous Secretary of the Royal Lifeboat Institution, or any one else who has paid attention to the subject, has to say about these lifeboats. If the thing be practicable, we see no reason why the ENGLISH MECHANIC Lifeboat should not be propelled on its beneficial errands by steam.

POPULAR

FOOD ANALYSIS.-
COCOA.*

(Continued from page 175.)
ET us see how far this dreadful programme is

at the following results of our analysis. But before doing so, we will explain the simple process we have adopted for obtaining our results. The mode of procedure does not pretend to absolute accuracy to a fraction, but will be found in practice easily performed and understood. It is as follows:

1. Twenty grains of the cocoa are weighed out and dried for some hours at a steam heat. The dry cocoa is then weighed, and the loss of weight, multiplied by 5, gives the moisture,

2. The residue (from 1) is digested for two hours, with frequent agitation, in four ounces of ether, and the latter having been poured off as closely as possible, the cocoa is again dried, weighed, and the loss of weight ascertained and calculated as above. The loss equals fatty matters.

3. The residue (from 2) is digested for six

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None.

Almost none,

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25 6.1 139 38.9 34.2 6-6

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26.2 42.1 7:0 14.7 334 39-5

Arrowroot.

Sago.

Arrowroot.
146 22.0 48 4 4.6
Red. Sago.
50 432 108 20-0 21-0 Grey. None.

It will thus be seen that, out of all the samples
examined, the only one which answers to the
analysis of pure decorticated cocoa is No. 21. Nos.
2 and 34 are, however, also good samples of cocoa,
while Nos. 11 and 12 must be noted as specimens
of pure cocon deprived of its oil. No. 1 is a pure
cocoa to which desiccated milk has been added,
thereby slightly increasing the fat and sugar. The
worst of all are Nos. 18, 19, 20, and 33, in which
not only is the quantity of real cocoa reduced to a
minimum, but ochre, or some such ferruginous
earth, has been added for colouring. On the whole,

the cocoa-consuming portion of the public. We
append recipes for the manufacture of cocoas
which would be similar to three of the most
adulterated samples:-
Cocoa... 100lb.
Sugar 40lb.
15lb.

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66

In our next article we will conclude the subject by giving directions, illustrated by engravings, for the detection of adulterations of cocoa, by means of the microscope.

THE PATENT LAWS.

A SHORT time since a meeting of the Man

chester Patent Law Reform Association was held, Sir William Fairbairn in the chair, when the following petition to Parliament was discussed and adopted :

"That your petitioners being persons engaged in various branches of industry and commerce in the city of Manchester and the surrounding district, formed themselves, with others, in 1850 into an association for procuring a reform of the patent laws as then existing and administered, the evils of which and the remedies therefor, they set forth in memorials to the Board of Trade and petitions to l'arliament in 1850, 1851, and 1852, and, after incessant labour and expense, were the principal means of obtaining the Patent Law Amendment Act of 1852. That Act, although it did not adopt all the recommendations of your petitioners, provided remedies for some of the then existing evils, such as granting immediate protection to inventors on application, a of

obtaining letters patent, and the publication of all specifications and indexes thereto; but it left untouched many of the evils for which your petitioners pointed out remedies, which had they then been provided for, would have satisfied the public and prevented the unreasonable outcry now raised for the entire abolition of the present patent laws. That your petitioners are fully of opinion that the fees may be considerably reduced, as they consider the cost of obtaining letters patent should not exceed what is absolutely necessary for the maintenance of the Patent Office and printing the specifications and indexes. That your petitioners, fully sensible of the advantages of a well-devised patent law, are decidedly of opinion that any attempt to abolish these laws would prove not only highly injurious to the best interests of the country, and destructive to the inventive powers of the nation, but would ultimately destroy the high position this country has attained in the prosecution of the

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