Of late many inquiries have been received which have been of such a character as to necessitate a few limitations in the "Correspondence" Department. We cannot give advice as to the merits and commercial possibilities of inventions and patents, or the sale of same, nor can we furnish designs of dynamos, steam engines, or flying machines upon requests written upon postal cards. It is also necessary that inquirers sign their names, as we are not mind readers and cannot reply if we do not know who makes the inquiries. Also, many of the inquiries are of such a nature as to require correspondence on our part, and it frequently takes some little time to procure the desired information. It is our intention, however, to make prompt reply by direct letter when a stamp is enclosed for postage.

A few inquiries regarding the reliability of some of our advertisers leads us to state that no advertisements are inserted in this magazine which we do not believe to be quite trustworthy. We accept no advertisements of doubtful character; in fact, have been accused of being over scrupulous, and feel confident that our readers will have no cause for complaint in any dealings which result from any advertisement appearing in the magazine.

We expect to be able to announce in the next issue a premium offer which we feel confident will be welcomed by a large number of our readers :-A servicable, efficient telephone for Two New Subscribers. The talking efficiency of these telephones will be fully equal to those of much higher price. They will have ringing bell, watch case receiver, switch hook, etc, and be well made in every particular. They will be just the thing for connecting the homes of two friends, from house to stable, or similar uses. We know they will be fully satisfactory, and advise our subscribers who would like them to secure the necessary subscriptions from their friends, which can be sent in advance and the premium sent when ready.

Do not delay ordering a set of the bound volumes ; they are going fast, and the supply of Vol. I. will soon be exhausted. The large amount of interesting and valuable information contained in these volume, makes their acquisition desirable while it is possible to secure them.

The steamship engineer carries great responsibility, and so much depends on him that any device that will facilitate his movements about the ship or aid him in his work is well worth installing. The "American Shipbuilder " suggests the need of elevators for the personal convenience of engineers in descending or ascending the 30 or 40 feet to and from the engine-room. The means of descent is ordinarily a slippery iron staircase where a firm grip, steady nerves and a sure foot are required to make it in safety. The elevator would cost little, as there is always plenty of steam or electricity at hand and plenty of room to spare.

Fir will grow at as great an altitude as 6700 feet above sea level, yellow pine at 6200 feet, ash at 4800 feet, and oak at 3350 feet. The vine ceases to grow at 2300 feet.