210 JMiscellanies. 
We are requested also to mention, that the patent right for the 
Congress powders and the recipe for preparing the magnesian ape- 
rient are for sale. Application for the purchase of them or of the 
cabinet can be made to Mr. Charles Conolly, at Cornelius Dubois 
Esq. of New York. 
10. Ewbank’s Tinned Lead-pipes.—Mr. Thomas Ewbank of New 
York, has invented a method of tinning lead pipes “after they have 
been drawn to the proper size.” This is ingeniously accomplished 
by drawing the lead tubes (properly prepared with rosin on their 
surfaces) through a bath of melted tin, kept at such a temperature as 
to avoid the fusion of the lead. . 
We have seen some of these tubes and their appearance promises 
a perfect protection to the lead. Should this, after sufficient trial, 
prove to be the fact, the discovery will ne of great importantce, espe- 
cially for aqueducts. ; 
We have just seen a oocian of a lead tube of two inches in di- 
ameter, which, having been laid down in alow meadow in Springfield 
Mass. where there are the remains of an ancient hemlock swamp, 
was, in the course of a few months, corroded through and through, 
and for this reason great expenses are incurred in taking up and 
replacing the spoiled tubes. We presume that the tinned tubes will 
not be liable to this accident. 
11. American Mangle or Domestic Callender.—This instrument, 
invented and patented by Mr. I. Doolitile of Bennington, Vt., we 
have seen used and we have conversed also with those who have 
employed it, and find that its use saves a great portion of the labor 
and all the fuel usually employed in the process of ironing table and 
bed linen, towels, &c. besides being much more expeditions and giv- 
ing the articles a better lustre and whiter appearance. It is regarded 
as a valuable auxiliary and by some is reckoned among the indispen- 
sable utensils of the laundry. We can confidently recommend it as 
a valuable acquisition to the conveniences of the family. 
12. Price of Platinum—Test Paper. 
Extract of a letter from Dr. Erastus F. Cooke, to the Editor, dated Wethersfield 
July 22, 1833. 
Dear Sir—In your reply to a letter of mine, (sometime since, in- 
quiring the price of platina,) you expressed a wish to know something 
of the result of my enquiry. I have to state, that I procured some 
friends to write to London and to Paris in relation to the subject, and 
I now send you the result. ‘ We have just received an answer from 
