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of merely finding the areas of figures; as the Learner immediately perceives the real use of the Science.

PART THE FIFTH contains the Mensuration of Solide, applied to finding the capacities of vessels of every de scription. Besides giving Rules for determining the contents of all regular vessels, of a known form; we have given the method of finding the contents of circular ves sels, with curved sides; when the nature of the curves cannot be ascertained. This we have done by means of equidistant parallel sections, founded on the method of equidistant ordinates. This Process is entirely new in a Book of Gauging; having never before appeared, except in Nesbit's Treatise on Practical Mensuration.' We have also given Rules for finding the contents of all cylindrical, pyramidical, and conical ungulas, that can possibly be formed, by placing, in various positions, vessels containing fluids. This has long been a desideratum in every Treatise on Gauging; and although these figures seldom occur in Practice, yet we are of opinion that every person who professes the art of Gauging, ought to be able to deter mine the capacity of any vessel or figure that can possibly be devised. This Part also contains One Hundred Mis cellaneous Questions, which will serve to exercise the ability of the Learner; and prove his knowledge of the Theorems and Rules given in the former part of the Work.

PART THE SIXTH is divided into Seven Sections; and comprehends the whole System of Practical Gauging, as adopted in the Excise. The first Section contains the method of gauging and fixing Victuallers' Utensils; the second that of gauging and inching Common Brewers' Utensils; and the third comprehends the method of gauging, inching, and ullaging Casks. As no part of the Science is attended with such difficulty as that of finding the contents of close vessels; we have bestowed much attention upon this part of the subject; and to the method of obtaining the contents of casks, according to their several varieties, we have added those of finding their contents, by General Rules, without paying any regard to their varieties.

Cask Gauging by the Callipers, Bung Rod, and Head Rod, as practised by the Port Gaugers of the Excise and

Customs, is also given in this Section. In this Part of the Work we have been ably assisted by a Gentleman who has had considerable Practice in the Excise Department of Port Gauging, at Newcastle-upon-Tyne. He also very kindly furnished us with a Manuscript containing many excellent observations on the method of taking the dimensions, making the allowances, casting the contents, &c. &c. For these favours we offer him our most unfeigned thanks.

The fourth Section contains the method of gauging and fixing Maltsters' Utensils; and the fifth that of gauging and inching the Utensils of Distillers. The sixth Section comprehends the method of gauging and inching the Utensils of Soap-Makers, Starch-Makers, and GlassMakers.

The seventh Section contains the Method of finding the areas and contents of vessels in Irish malt bushels and liquid gallons; and of reducing Irish to English, and English to Irish measure; thus the Work is adapted for Ireland, as well as for England and Scotland. This Section also contains a Table of the Specific Gravities of bodies; the method of finding the magnitude of a body from its weight, or the weight of a body from its magnitude; and likewise the process of determining the tonnage of Ships, according to the Parliamentary Rules.

PART THE SEVENTH is divided into three Sections. The first contains a Table of Ale Areas; the second a Table of Wine Areas; and the third a Table for reducing Ale Gallons to Victuallers' Barrels.

Besides the regular subjects enumerated in the Table of Contents, the Work is interspersed with numerous Notes, Remarks, and Observations, which will tend greatly to elucidate the Subject. The leading features of these Remarks we will just notice in a cursory manner. Part the Sixth contains copious directions for taking the dimensions of all kinds of vessels that can possibly be met with in the Practice of Gauging. This is of the greatest importance; for it is evident that if the dimensions be improperly taken, the results must always be incorrect; notwithstanding the greatest accuracy may be used in finding the areas and contents.

Every possible attention has been paid to the method of gauging and fixing the Utensils of Victuallers; and to gauging and inching those of Common Brewers; and numerous Examples have been given to illustrate the method of entering the dimensions and areas; and forming the Table Books, as practised by Officers of the Excise. On Cask Gauging we have made several Remarks, Observations, and Comparisons, which will tend to elucidate that subject; and point out the impropriety of gauging all casks as belonging to the first variety.

Malt Gauging is treated of very extensively; and every information has been given, that we thought necessary on that subject. The method of gauging Stills, and StillHeads is rendered as simple as possible; and that of gauging and inching oval Wash-backs, and Jack-backs, by means of equidistant ordinates, is treated in a clear and perspicuous manner. The methods of gauging Soap and Glass have never before appeared in any Work on this subject; and will therefore be found very acceptable to all those who are concerned in the manufacturing of these articles.

In finding the areas and contents of vessels, we have not only used the Pen, and the Sliding Rule; but also the Tables of Ale and Wine Areas given in Part the Seventh. As the Sliding Rule is much used by Officers of the Excise, we have given clear and perspicuous Rules for its application, whenever it could be introduced with success. The Tables of Ale and Wine Areas we have taken from Mr. Moss's Gauging; they being more correct than any other that have fallen under our notice. They generally give the areas of circles rather more than the Rule by the Pen; but sufficiently correct for every Purpose of Practi cal Gauging.

The Questions given in each Problem, for the Exercise of the Learner, form one of the most prominent features of the Work; and completely distinguish it from all others on the same subject. These Questions will be found of infinite service in Schools; and are what Teachers have long desired; for it is impossible to make young persons comprehend any subject properly, without giving them Line upon Line, and Precept upon Precept.

Notwithstanding a person may possess the most brilliant talents; that he may comprehend general arts and sciences in all their ramifications; and that long practice may have made him familiar with particular subjects; yet it will readily be admitted that he will find some difficulty in retaining every minutia relating even to those sciences with which he is most intimately connected. Taking these things into consideration, we are persuaded that the following Work will be found useful, not only to Learners, but also to those persons who are already acquainted with the subject of Gauging; and we hope it is executed in such a manner, and treats so extensively of the Science, in all its Departments, that even Experienced Officers of the Excise and Customs will not find it unworthy of their Notice, as a Book of General Reference.

Having taken a survey of the subsequent Work, and made such introductory observations as we thought necessary; it now only remains for us to solicit the indulgence of the Public, for any errors that may have escaped our notice.

As the Work is entirely new, we do not expect that it will be found quite free from imperfections; however, we can assure our Readers, that neither labour nor pains have been spared in order to produce such a Treatise on Practical Gauging, as may be found worthy of General Patronage.

Bradford, Yorkshire,
June, 1822.

A. NESBIT.

W. LITTLE.

P. S. A Key to the Practical Gauging is in the Press; and will be published in a few Weeks.

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